ASP.NET Performance Optimization


The Performance of an application from the perspective of the client is very important and if it is degraded from too many round trips, too many resources, too many ajax or server calls, it gives the end user no option other than leaving your useful resource. So to end this problem you must have an eye on ways to boost your application performance by using performance boosters.

Performance of an application is the most important aspect which you need to monitor every day to provide uninterrupted services to your favorite clients and the better approaches your system uses the better results you will get. I will write the series of Optimization and Performance Techniques for SQL, jQuery, Ajax, JavaScript, C#, query optimization, and Website Optimization in upcoming articles but for now I am stating ASP.NET Performance Metrics.

But wait, what are the ways that you can judge how you want optimization of your web / application?

Below is the list of Optimization and performance Metrics that you want to acknowledge.

  1. Speed
  2. Use Logs
  3. Proper Exception Handling
  4. View State
  5. Proper Use of Caching
  6. Avoid Serve Side Validation
  7. Minify and Compress JS, CSS Resources
  8. Session Management
  9. Paging for Large Result set
  10. Avoid Un-necessary RoundTrips to Server
  11. Pages Must be Batch Compiled
  12. Partition Application Logically
  13. HTTP Compression
  14. Resource Management
  15. String Handling

We Can Discuss Each one in detail. So let’s start.

Speed

Speed of your application is the most important factor and you need to keep an eye on this factor. There are many factors involved to boost speed of your application:

Reduce Page Size:

  • By Reducing page size by means of using external css and javascript files instead of inline css and javascript.
  • The other way to reduce page size is to used only the minify version of javascript files and also beautify css and js by online tools.

To beautify Cascading Style Sheet Files Follow this Link.

To beautify Javascript files follow this Link.

To Minify Cascading Style Sheet Files Follow this Link.

To Minify JavaScript files follow this Link.

Beautify means to format the unformatted files (means with white space, comments and without indentation).

Minify means to remove white spaces, comments, non-indent text and the nice feature is to reduce space by giving your functions and variables a single name like function a(b){ if b == ‘4’){ b=’good’}}, move your code to single line of function defined.

  • Its very efficient way to separate the logic of your page as well as we did to crate an application by separating the logic of data access and business layers, so in page level you can separate it by making user controls of header, body and footer.

Reduce No of Requests to Server:

The fewer number of requests served to the server the more efficient your page behavior is.

Reduce the number  of requests by reducing the number of resources, like move your inline css code of all files to single css and like wise with javscripts. The other way is to cache the non static resouces and remove unnecessary headers from requests like version number and asp.net powered by. Use CDN (Content Delivery Network) so that it downloads files from nearest available server and save the concurrent requests if other websites are using same jquery plugin files.

Use Logs

Use IIS Log to trace out issues on weekly or monthly basis of your application, and the best is that you have to watch it on adaily basis, mainly IIS Log contains information about your server , date and time span, Referral page and the original URL and lots more information and also the HTTP Status response codes through which you can understand the nature of the issue.

I have written post on HTTP Status Response code you can read it from Here

The other way you can customize what to log is by creating a database table and inserting the exception detail in this, I have done it this way in my organization and also tracking module which can search, generate report on daily basis, insert the log modules and lots more, so that you don’t need to query the table again and again to check for daily error or for reporting.

There are other best approaches to track the error, one of the best available tools is Elmah Tool, which has a config base setting through which you can track it by configuring it with email option to the responsible person.

ELMAH (Error Logging Modules and Handlers) is an open source debugging tool for ASP.NET web services. When added to a running web application on a machine, exceptions that are thrown trigger event handlers in the ELMAH tool.

You can get it from google code Link OR

You can get it from Nuget Packages Link.

Proper Exception Handling

There are many developers who cannot handle proper exception techniques as a result the final outcomes are not pretty satisfied which means they cannot understand if there is any crashing of the application. The best way is to use try….. catch block appropriately to handle the exception in a right manner. User can use (if statement) to check for open connection if not open close the connection to the database. The other way use can use the (try…. catch block) for the connection if not closed throw an exception. With try…catch it is best approach to use finally block also with try…catch and then block like this to properly dispose off the unused resources if exception occurs or not.

  1.  try
  2.  {
  3.  }
  4.  catch (Exception)
  5.  {
  6.  throw;
  7.  }
  8.  finally
  9. {
  10.  }

Exception handling is the most important technique for finding the original run time unhandled exception in application but it should be wisely and judiciously used.

View State

View state is encrypted component in webforms that maintain the state of pages. It is used to maintain the state of page in post backs, these are the hidden fields and you can check by viewing source of page. iI you are too using the view state to maintain the state behavior of data in web forms in large form it loads your page and as a result you have a performance issue.

The potential issues lies with view state; it has large page load times due to increased number of page states.

So what are the best practices to override these types of headoff.

Here are some performance paradigms that must be accounted for while using view state.

  • Use it whenever needed in a page but limited it to small size as possible.
  • Don’t use multiple forms in a single page having state management enabled.
  • Use it wisely required on page or either in control level to application level.
  • Monitor the size of view state by enabling tracing.
  • Avoid storing large objects as the size is directly proportional to the objects.

Proper Use of Caching

With the proper use of caching you can get a lot of benefits like reducing the round trips to the server, reducing the number of server resources and it renders faster than in routine normal mode. It can improve the performance manyfold by caching the data on multiple Http Requests, it can store the page partially for specified times with some expiration values. It can boost application performance by storing data in memory so that it can be accessed quickly with less time just like CPU RAM. Cache can be accessible in your single application to use in webfarm you can use the distributed cache managers like memcached to share the cache data within the web farm.

Best use of cache is as follows:

  • Use it in all layers DataAccess, Business and UI Layer and use it in a proper way can give you performance boost.
  • caching for large time for static resources or not too used resources and also adding expiration to cache also give best performance.
  • Don’t cache expensive objects in cache like connection and like other resources.
  • use Output cache for static pages with expiration time and location as per your need.
  • Use partial fragment cache to partially cache the page component.

Avoid Server Side Validation

Validating your system is an important part as you filter what you want very clearly in DB because if you have free type text input then chances are that the required data cannot be received that’s why validations are required.

Validations are of two types: Client and server side validation.

Server Side Validation are important by the perspective of securing your sensitive information like saving password and other sensitive information. This is always not required to do server side validation as it always submits request and response back to client which causes in the cost and time of the user. This type of validation occur when submit is Hit.

Best Tips is to use whenever you required to ensure that security is not bypassed otherwise it is better to check the client side validation formats like email, URL , phone number, masking and other required information which need to be correct.

Minify and Compress JS, CSS Resources

The best approach with static content files is to minify which means make them small. Just like in production environment Jqueryis also recommended to use the min.js version file for best operations with their library you need too to include the minified version of your application working javascript files as the number of requests greatly increases the page time as some time size of file doesn’t matter but it can also be reduced by using the minified files for javascript and CSS files.

In IIS there is also setting for Compressing the Static and dynamic content you can too try this to enable compression in website.

This is also the best approach to use the Cascading style sheet files in the head of the webpage while the scripts must be included in the bottom of the page for fast processing of the page.

As you all aware of that we are using bundles of javascript libraries day by day to do our work but we foget about the behavior and impact which they made to our system. To overcome this Microsoft also announced its Microsoft web Optimization framework which is also useful.

You can read more about this framework from Here.

You may refer to section 1 of this article about the speed concerns.

Session Management

Session is an important part for asp.net applications but its effects are adverse if not handled properly.

Here are some best practices to use it intelligently.

  • Do not store a bunch of data in sessions.
  • Store basic types of data not complex types likes object.
  • Use wisely the available session states like in Proc, out of process using state view and out of process using SQL Server.
  • Out of process is the best option as it application did not restart despite of any application configuration changes but it is slow as it is some server of in sql, While the other in proc is fast as it is used same memory as application and their retrieval is also fast.
  • Do not use sensitive data in session state.
  • Always use abandon () method to sign out the user with session enabled.

Paging for Large Result set

Paging on large result sets are an extremely useful approach as we restrict the result to 10 to 30 records per page to be shown and on call of next records we get more records to load it reduces the extra load server bear to fetch all the records and return it which causes increase in page load times and extra cost to your users as well as the whole page goes unresponsive for about large time. So best approach it to make your result sets as less as possible and also use of ROWCOUNT() enhances the paging a lot more.

As your client has low resources either saving the large results set also make impact on your client.

The basic backbone in paging is the use of row_number ranking function. If you can check time with all records versus no of first page records than it show a great improvement.

Avoid Un-necessary Roundtrips to Server

The best method to avoid roundtrips to the server is to ensure that no un-necessary calls sent to the server as number of requests sent to the server increases the page load time increase in the result client suffers.

So it is necessary that you must use client mechanisms to ensure the validity to get data from server as it does not result in post backs and not involve any server callbacks which result in server involvement and it trigger the request response cycle.

You can following metrics to minimize the round trips between web server and browser.

Use Server.Transfer instead of Response.Redirect for redirecting to certain path. Server.Transfer scope is in current application redirection for redirecting to other than your application use Response.Redirect.

If your data is static you can use caching for best performance. Use Output Buffering as it reduces roundtrips by loading whole page and made available to client. If you want to transfer some data and client always connected then use HttpResponse.IsClientConnected as it reduces chances of any missing change not sent to server.

Pages must be Batch Compiled

The more the assemblies grow in a process, there are more chances that process shoots out and it throws out of memory exception. To overcome this pages need to be batch compiled as when first requested is initiated to compile pages all the pages in the same directory batch compiled and it make a single assembly. The basic advantages is thatthe  max number of assemblies that try to load in the process does not load which did not compromise on server load and only single batch compile assembly loaded in the process.

You can also ensure some things while doing this like:

  • Debug property in the configuration file always set to false in the production environment as if it is set to true pages are not batch compiled
  • Pages also did not time out if certain web service of page is not responding at the desired time,
  • Make sure that different languages are not used in same directory as it reduces chances of batch compilation.

Partition Application Logically

This means logically partitioning of your application logic like business, presentation and Data access layers. This is very useful as you have control of anything happening in any one can do their respective work in logic layer. This didn’t mean that you have to write more line of code, proper code with reusability and scalability of the application is the key properties of your application overall performance.

Don’t confuse it with physical separation of logic, as it only separate the code logic.

Below are the key pros of the separate application logic.

  • The main advantage of this is that you have a choice of logic to be separately reside on servers for your easiness in a web farm environment but it increase the latency of calls.
  • The closer is you logical layers the more benefit you have for example the all logic files in bin directory.

HTTP Compression

As the name suggests that http compression means to compress the content mostly in Gzip format or deflate and send with content headers after compression applied. It provides faster transmission time between IIS and browser.

There are two types of compression supported in IIS:

Static Compression:

It compresses cache static content by specifying in the path of directory attribute. After the first request that is compressed followed by requests used the cache compress copy thus decrease the time to furnish the content and increases productivity and performance of application. You should only compress the static content which is not changes not dynamic one.

Dynamic Compression:

Unlike the static content, dynamic content often changes as a result it supports compression by not being able to add in to the cache it only compresses the content.

Resource Management

The resource management is the management of overall resource of your application as it directly related to the performance of the application. Poor resource management decreases the performance and it loads your server CPU.

Below is the list of the most useful techniques for resource management.

  • Good use of pooling
  • Proper use of the connection object.
  • Dispose of unused resources after using them
  • Handling memory leaks.
  • Remove unused variables

String Handling

String management is one of the key to manage the memory of your application.

There are many techniques which is very useful in handling strings, some of them are enlisted:

  • Use Response.Write() to fastest show output to the browser.
  • Use stringBuilder when you don’t know the number of iterations to concatenate strings.
  • Use += operator to concatenate string when you know the number of strings are limited.
  • Do not use .ToLower() while comparing string as it creates temporary string instead use the string.compare to compare two strings because it has built in check for case insensitive data by using cultureinfo class.

Visual C# Built In Code Snippets For Fast Productivity


Code snippets are ready made, which means they are really useful reusable codes which need to be used and then again used at someother  part of work.

These snippets are not really of the type which are only used by just placing a cursor and inserting it to the place you want, but some are surrounded with code snippets also in which some line of code has been selected and then surrounded with required if statement, for loop and so on.

Code Snippets have following Advantages:

  • It saves a lot of your time by saving reusable code in code snippet manager and you can later use it anywhere.
  • It increases productivity by simply inserting code in you desired location.
  • It reduces the chances of less error by re typing your line of code.
  • It helps to stream line your work as per you assigned deadline.

Code Snippet Manager:

Firstly, you can check a whole list of code snippets in code snippets manager which you can open by pressing Combination of (Ctrl + K, Ctrl + B).

You can alternatively open code snippet manager from Visual Studio Menu from Tools è Code Snippets Manager…

There is another way to open as introduced in latest versions of visual studio which is very beneficial to open the menu items in less time; it is the Quick Launch Search Box Displayed in Top Right of your Visual Studio IDE.

As you type text it gives you suggestions and suggestions to do more actions also, like it displays the most Recently used items and Nuget Package Manager search for the searched keyword.

How to Use Code Snippets:

Basically there are two types of code snippets to be used; First one is by placing cursor at location and typing some code snippet code and secondly by using surround-with code snippets.

Note: At any time if you do not want to select the desired code snippets Press ESC Button it will dissolve and does not insert the code snippet.

Cursor Based Code Snippets:

Usage of code snippets is very simple. Just place cursor at the desired location where you want to insert code snippets, type snippet code and Press TAB Button Twice to insert in the place… we will discuss full list of code snippets in this article after following this but for reference I am quoting here an example of code snippet… for example you want to add for loop, just write for and press twice to check the magic of code snippet inserting and with full syntax and with default values. It Increases your productivity and time by also reducing the risk of human errors while creating complex syntax like for loop.

You can use it from Keyboard shortcut also by pressing key combination of (Ctrl + K, Ctrl + X) and select the Visual C# Category.

But if you have to remember the snippet code you can type it.

Surround-With Code Snippets:

You can use surround with code snippets by selecting the line of code and press keyboard short cut key combination (Ctrl + K, Ctrl + S) and type the desired code snippet to wrap in the line of code.

List of Available Code Snippets:

Now we will move into the using of code snippets inside IDE.

#region:

Region directive is used to define certain region in the code which specifies certain functionality or scope of certain work. It is collapsible portion and it is useful for pages which has lengthy code written so that you can collapse the region of code and focus on your work.

The start #region must be terminated with #endregion directive otherwise it will through the exception.

#region has a scope of anywhere means you can insert it anywhere you want.

(~):

This code snippet has scope only in class as class has destructors.


As already mentioned that has scope with in class so I checked it with creating outside the scope of class, although it created as it is snippet but it will generate compile error or a namespace cannot directly contain members such as fields or methods, while the other one inside the class scope did not through any exception.

ctor:

This code snippet is used to create constructor of a class. It has also scope within class otherwise it generate exception.

Type ctor and press TAB twice to insert.


class:

This snippet will create a declaration of class. It has a scope of namespace (global), class or struct.

enum:

This is used to declare enumeration. This is used to build a list of distinct enumerators. It has a scope of inside namespace, class or struct. The default value for initial first enumerator is 0 and the successive items will follow it like 0, 1 and so on. Enums cannot contain whitespaces while declaring their names.

The approved types of enum are int, long, byte,unit,ulong,ushort,short and sbyte.


cw:

Very helpful snippet cw means Console.WriteLine() which can show current line terminator to the output stream. Its scope lies inside method, indexer, property or event accessor.

It can take string as a parameter and return to output stream. You can align string to New Line also by using Console.Out.NewLine,

  1. Console.WriteLine();

equals:

The Equals as the name defined it has behavior to check equal of two objects either they are of same type or of different type and it returns Boolean value, if matched it return true otherwise false.

Its scope lies only inside class or struct.

  1. // override object.Equals
  2. public override bool Equals(object obj)
  3. {
  4. //
  5. // See the full list of guidelines at
  6. // http://go.microsoft.com/fwlink/?LinkID=85237
  7. // and also the guidance for operator== at
  8. // http://go.microsoft.com/fwlink/?LinkId=85238
  9. //
  10. if (obj == null || GetType() != obj.GetType())
  11. {
  12. return false;
  13. }
  14. // TODO: write your implementation of Equals() here
  15. throw new NotImplementedException();
  16. return base.Equals(obj);
  17. }
  18. // override object.GetHashCode
  19. public override int GetHashCode()
  20. {
  21. // TODO: write your implementation of GetHashCode() here
  22. throw new NotImplementedException();
  23. return base.GetHashCode();
  24. }

exception:

Creates a declaration for class that derives from exception by default. Exceptions are errors which are generated by the application. Its scope is inside a namespace, class or struct.

  1. [Serializable]
  2. public class MyException : Exception
  3. {
  4. public MyException() { }
  5. public MyException(string message) : base(message) { }
  6. public MyException(string message, Exception inner) : base(message, inner) { }
  7. protected MyException(
  8. System.Runtime.Serialization.SerializationInfo info,
  9. System.Runtime.Serialization.StreamingContext context)
  10. base(info, context) { }
  11. }

for:

for statement is most probably used to run together block of statements in a repeated fashion until you statements return false. The best possible scenario for using for loop having you know number of iterations required to get possible operation.

  1. for (int i = 0; i < length; i++)
  2. {
  3. }
foreach:
foreach iterates through for each element in an array or object collection that implements IEnumerable or Generic IEnumerable Interface.
It just iterate to the collection of items but it does not for adding or removing items. you can use break and continue operation inside foreach loop as per your easness.

  1. foreach (var item in collection)
  2.         {
  3.         }

for:

this code snippet is for decrementing values  after each iteration using for loop. Its scope is as same as for loop.
  1. for (int i = length – 1; i >= 0; i–)
  2.        {
  3.        }

if:

it is the most important and too many used code snippet in daily work routine. due to its  simplicity its as important as you think you have to include for every block statement to check for. It has scope inside a method, indexer, property or event accessor. by default it has true value like we are checking for check box which is either checked or not so that we can evaluate the if … else condition on the base of it.

  1. if (true)
  2.         {
  3.         }

Interface:

by inserting this snippet it create the interface declaration. an interface only contain the signature of methods, indexer,events pr properties. a class which implements the interface must used the members which interface has defined.  An Interface can inherit from one or more base classes. it has scope inside a class, struct or namespace (global).

  1. interface IInterface
  2. {
  3. }

namespace:

it declare a scope / set of related objects. inside a namespace you can declare one or more namespace,c lass, struct, enum, interface and delegate.

it has scope only inside namespace which has global scope.

  1. namespace MyNamespace
  2. {
  3. }

prop: it created auto-implemented property inside a class or struct.you can initialize certain properties with some initial value.

  1. public int MyProperty { getset; }
propfull: it can create property declaration with get  and accessors and it has scope only inside a class or struct.
  1. private int myVar;
  2.     public int MyProperty
  3.     {
  4.         get { return myVar;}
  5.         set { myVar = value;}
  6.     }

switch:

It is a control statement which selects a switch section and break no succeeding section should be checked. each switch section contains one or more case labels followed by one or more statements depending on the scenario.

  1. switch (switch_on)
  2.         {
  3.             default:
  4.         }

try:

create a try….catch block. the most important purpose of try … catch is to catch unhandled exceptions by trying a block of code and it successful it moved to the next section or move out of the method block and if not successful it go to the catch section where customized as well as other exception are thrown to identify the type of breakage caused by the try code.

  1. try
  2.        {
  3.        }
  4.        catch (Exception)
  5.        {
  6.            throw;
  7.        }
tryf: the basic purpose of using finally with try block is to cleanup the resources which is occupied by try block,
  1. try
  2.         {
  3.         }
  4.         finally
  5.         {
  6.         }
while:

It executes block of statements until the expression is not set to false. The executing statement can also be terminated by adding break, go to like statements. It has scope inside a  method, indexer, property or event accessor.
  1. while (true)
  2.        {
  3.        }
That’s all about some of the useful code snippets but there are some others; you can check full code snippets  manager for full list.

Bind GridView Using DataTable


In this article I will cover the basics of creating DataTable to get data and fill into the ASP GridView Control to fill, bind, and show the data.

Step 1: Firstly, we need to create an empty project by opening Visual Studio by pressing commanddevenv in the Start menu search bar or using Windows Run-Command by pressing (Windows icon + R ) and enter devenv. It will open the installed version of Visual Studio.

If by pressing this opens the old one, you can change it by changing the registry value for updated version by following this link.

Step 2: Now after opening Visual Studio you can create new a website by going to File, New, thenWebsite or by pressing Shift+Alt+N command in Visual Studio.
Step 3: Now give a name to the project and also select desired location of website.
Step 4: Now create a new web form by pressing combination of keys (Ctrl + Shift + A).

 
Step 5: Now we first add GridView control to the Web Form.

  1. <form id=“form1” runat=“server”>
  2.      
  3.          “gvitems” runat=“server” AutoGenerateColumns=“false”>
  4.              
  5.                  “ItemId” HeaderText=“Item ID” ItemStyle-Width=“30” />
  6.                  “ItemName” HeaderText=“Item Name” ItemStyle-Width=“150” />
  7.                  “ItemQuantity” HeaderText=“Item Quantity” ItemStyle-Width=“150” />
  8.              
  9.          
  10.      
  •  </form>
  • Note: (Possible Exceptions)
    1. Make sure that GridView control must be placed in <form> tag with runat=’server’ attribute.
    2. Another thing  which you need to take care of is that you must use AutoGenerateColumns=”false”.
    If you are using custom columns which are binding date the you must set this attribute to false otherwise see the image for reference.
    As you can see the columns repeated by default, it is set to true when you set it to false and  it come to its original position of number of assigned columns.
    Step 6: Import the required Namespace.
    1. using System.Data;
    Step 7: Now we can write the ADO.NET server side code to generate columns, add new values to row and finally bind it to the GridView.

    1. if (!Page.IsPostBack)
    2. {
    3.     DataTable dt = new DataTable();
    4.     dt.Columns.AddRange(new DataColumn[3] { new DataColumn(“ItemId”typeof(int)),
    5.                     new DataColumn(“ItemName”typeof(string)),
    6.                     new DataColumn(“ItemQuantity”,typeof(string)) });
    7.     dt.Rows.Add(1, “Flour”“500 Kg”);
    8.     dt.Rows.Add(2, “Tea”“20 Kg”);
    9.     dt.Rows.Add(3, “Rice”“1000 Kg”);
    10.     gvitems.DataSource = dt;
    11.     gvitems.DataBind();
    12. }
    Let’s elaborate code one by one.
    1. DataTable dt = new DataTable();
    Initialize the new instance of DataTable class by new Keyword.
    1. dt.Columns.AddRange(new DataColumn[3] { new DataColumn(“ItemId”typeof(int)),
    2.     new DataColumn(“ItemName”typeof(string)),
    3.     new DataColumn(“ItemQuantity”,typeof(string)) });

    Add columns to the array to the end of collection.

    1. dt.Rows.Add(1, “Flour”“500 Kg”);
    2.             dt.Rows.Add(2, “Tea”“20 Kg”);
    3.             dt.Rows.Add(3, “Rice”“1000 Kg”);

    Create a new row with specified values and add to the data row collection.

    1. gvitems.DataSource = dt;
    Gets or sets the object from which the data-bound control retrieves its list.
    1. gvitems.DataBind();
    Bind the DataSource to the GridView control.
    Step 8: Final Output
     

    Export To Excel Data By LINQ to SQL


    There are many times we require certain reports to be exported to certain require Files i.e Export to Excel, PDF and CSV but for today we can see how we can export to excel with querying to database through LINQ to SQL query.

    So let’s start to build interface buttons which will do the rest of work to query and export to excel.

    1. <asp:Button ID=“btnGetData” runat=“server” Text=“Export to Excel” OnClick=“btnGetData_Click” />
    This button has OnClick (btnGetData_Click) Event which will fire when we click on it, before starting we will add the following references to the project. on the upper section where reference are defined and also by adding in the Reference folder of solution.

    1. using System.Web;
    2. using System.Drawing;
    3. using System.Reflection;
    4. using System.Data;
    5. using System.Linq;
    6. using OfficeOpenXml;
    7. using OfficeOpenXml.Style;
    8. using OfficeOpenXml.Table;
    Now we will write the backend logic of button.
    1. protected void btnGetData_Click(object sender, EventArgs e)
    2. {
    3. DataTable dt = new DataTable();
    4. List<NewsFeed> NewsFeeds = (from emp in db.NewsFeed select emp).ToList<NewsFeed>();
    5.             if (NewsFeeds.Any())
    6. {
    7. ListtoDataTableConverter converter = new ListtoDataTableConverter();
    8. dt = converter.ToDataTable(NewsFeeds);
    9.                 ExportExcel(dt);
    10. }
    11. }
    Now I will explain the line of code as you can see we have a button event which will fire on click.
    FIrst of all we create DataTable and initialize it on the start which will hold the converted data.
    1. DataTable dt = new DataTable();
    Now we have write the linq to sql query and all the result which will fetch through query is moved to the list.
    1. List<NewsFeed> NewsFeeds = (from emp in db.NewsFeed select emp).ToList<NewsFeed>();
    After that we will check as a best practice, is there any data returned by the query by writing line of code like this
    1. if (NewsFeeds.Any())
    2. {
    3. }
    If list variable contains any thing we have use .Any() as a best practice to check the content length otherwise you can use .Count() method too to check for any count of returned row to do the rest of processing.
    1. if (NewsFeeds.Count())
    2. {
    3. }
    Now we will create new class and initialize it to convert the list structure to datatable to ease our work as per our requirement.

    1. ListtoDataTableConverter converter = new ListtoDataTableConverter();
    Complete class is elaborated below.
    1. public class ListtoDataTableConverter
    2.  {
    3.  public DataTable ToDataTable<T>(List<T> items)
    4. {
    5.  DataTable dataTable = new DataTable(typeof(T).Name);
    6. //Get all the properties
    7.  PropertyInfo[] Props = typeof(T).GetProperties(BindingFlags.Public | BindingFlags.Instance);
    8.  // Loop through all the properties
    9.  foreach (PropertyInfo prop in Props)
    10.  {
    11.  //Setting column names as Property names
    12.  dataTable.Columns.Add(prop.Name);
    13.  }
    14.  foreach (T item in items)
    15. {
    16.  var values = new object[Props.Length];
    17.  for (int i = 0; i < Props.Length; i++)
    18.  {
    19.  //inserting property values to datatable rows
    20.  values[i] = Props[i].GetValue(item, null);
    21.  }
    22.  // Finally add value to datatable
    23.  dataTable.Rows.Add(values);
    24.  }
    25.  //put a breakpoint here and check datatable of return values
    26.  return dataTable;
    27.  }
    28. }
    I have elaborate every piece of code with comments what is going on while converting list to dataTable. We are using the DataTable method to convert it to the datatable from list inside classListtoDataTableConverter.
    1. dt = converter.ToDataTable(NewsFeeds);
    Finally, we will use the Export to Excel function by allocating the content type to convert it to the appropriate format. We will call export method and pass converted dataTable from list.
    1. ExportExcel(dt);
    For conversion to excel purpose I am using microsoft built in library called open office XML Extension.

    Right click on References folder of project and select Add Reference.

    Add below highlighted Extensions in to the project.

    Add This Method to File.
    1.  private void ExportExcel(DataTable dt)
    2.    using (ExcelPackage pck = new ExcelPackage())
    3.   {
    4.   // Excel Sheet name
    5.   ExcelWorksheet ws = pck.Workbook.Worksheets.Add(“ExportReport”);
    6.   // pass the cell from where we start dumping data and load the data from datatable
    7.  ws.Cells[“A1”].LoadFromDataTable(dt, true, TableStyles.Medium15);
    8.  //Read the Excel file in a byte array
    9.  Byte[] fileBytes = pck.GetAsByteArray();
    10.  HttpContext.Current.Response.ClearContent();
    11.  // Add the content disposition (file name to be customizable) to be exported.
    12.  HttpContext.Current.Response.AddHeader(“content- disposition”,“attachment;filename=Exported_” + DateTime.Now.ToString(“M_dd_yyyy_H_M_s”) + “.xlsx”);
    13.  // add the required content type
    14.  HttpContext.Current.Response.ContentType = “application/vnd.openxmlformats-officedocument.spreadsheetml.sheet”;
    15.  // write the bytes to the file and end the response
    16.  HttpContext.Current.Response.BinaryWrite(fileBytes);
    17.  HttpContext.Current.Response.End();
    18.  }
    Code Elaboration:
    1.  // Excel Sheet name
    2.   ExcelWorksheet ws = pck.Workbook.Worksheets.Add(“ExportReport”);
    3.   // pass the cell from where we start dumping data and load the data from datatable, also you can add styling by using table style and check name from excel file for required design
    4.   ws.Cells[“A1”].LoadFromDataTable(dt, true, TableStyles.Medium15);
    5.   //Read the Excel file in a byte array
    6.   Byte[] fileBytes = pck.GetAsByteArray();
    7.  // Add the content disposition (file name to be customizable) to be exported.
    8.  HttpContext.Current.Response.AddHeader(“content-disposition”“attachment;filename=Exported_” + DateTime.Now.ToString(“M_dd_yyyy_H_M_s”) + “.xlsx”);
    9.  // add the required content type
    10.  HttpContext.Current.Response.ContentType = “application/vnd.openxmlformats-officedocument.spreadsheetml.sheet”;
    11.  // write the bytes to the file and end the response
    12.  HttpContext.Current.Response.BinaryWrite(fileBytes);
    13.  HttpContext.Current.Response.End();
    Final Output

    Filter An Array of Different Data Types by Array Filter Method


    We use arrays to store multiple values in a single variable and retrieve, filter or remove as per our need.
    Firstly, we can understand in which condition we can use array; basically, if you have more than one value, like a list of items of store, or some values like status of task such as pending, in progress,or completed.
    But if you have different types in an array like string, number, or boolean values and you want to filter them by some type then you can use the array filter method.
    The typeof operator in JavaScript returns “object” for arrays. Arrays use numbers to access its “elements”.
    So, lets start with an array of different types:
    1. var arrtest = [];
    2. arrtest.push(“One”);
    3. arrtest.push(“Two”);
    4. arrtest.push(false);
    5. arrtest.push(3);
    6. arrtest.push(“THree”);

    Firstly, push values of different types to array and the final result of array look like the following:

    1. [“One”“Two”false, 3, “THree”]
    Now we will apply the filter method to filter the array for specific type.
    1. arrtest.filter(filterByNumber);
    As you can see we have applied filter method and pass function which can filter by number and return the array with specific type.
    1. function filterByNumber(obj) {
    2.     if (typeof (obj) === ‘number’) {
    3.         return true;
    4.     } else {
    5.         return false;
    6.     }
    7. }
    In this function we use typeof to return the matching number in the object.
    The final output is:
    1. [3]

    You can use the filter method and apply typeof to filter the specific type. For more information about typeof operands you can see the documentation here.

    Convert HTML String To PDF Via iTextSharp Library And Send As An Email Attachment


    In this article we will see how we can convert string of data to PDF and then send email with attached copy of generated PDF.
    Firstly, we can convert the string of data to PDF by using Popular Library for rendering PDF is ItextSharp. Secondly, we can attach the converted PDF file to email and send to the recipient by using built in C# Mail messages Class.
    So, lets start to  build our first step,
    Step 1: Convert  HTML String to PDF,
    In this step we will first create button which will do the rest of work on Click event.
    Let’s create the button to perform the required operation.
    1. <asp:Button ID=“btn_PDFEmail” runat=“server” Text=“Convert HTML to PDF and Send Email with Attachment” OnClick=“btn_PDFEmail_Click” />

    The UI view looks like the following:

     
    So our front end is all set and we need to apply the cs logic to perform operation.
    Let’s start building HTML string.
    1. StringBuilder sb = new StringBuilder();
    2.                    sb.Append(“<header class=’clearfix’>”);
    3.                    sb.Append(“<h1>INVOICE</h1>”);
    4.                    sb.Append(

      );

    5.                    sb.Append(
      Company Name

      );

    6.                    sb.Append(
      455 John Tower,
      AZ 85004, US

      );

    7.                    sb.Append(
      (602) 519-0450

      );

    8.                    sb.Append(

      );

    9.                    sb.Append(“</div>”);
    10.                    sb.Append(

      );

    11.                    sb.Append(
      PROJECT Website development

      );

    12.                    sb.Append(
      CLIENT John Doe

      );

    13.                    sb.Append(
      ADDRESS 796 Silver Harbour, TX 79273, US

      );

    14.                    sb.Append(

      );

    15.                    sb.Append(
      DATE April 13, 2016

      );

    16.                    sb.Append(
      DUE DATE May 13, 2016

      );

    17.                    sb.Append(“</div>”);
    18.                    sb.Append(“</header>”);
    19.                    sb.Append(“<main>”);
    20.                    sb.Append(“<table>”);
    21.                    sb.Append(“<thead>”);
    22.                    sb.Append(“<tr>”);
    23.                    sb.Append(“<th class=’service’>SERVICE</th>”);
    24.                    sb.Append(“<th class=’desc’>DESCRIPTION</th>”);
    25.                    sb.Append(“<th>PRICE</th>”);
    26.                    sb.Append(“<th>QTY</th>”);
    27.                    sb.Append(“<th>TOTAL</th>”);
    28.                    sb.Append(“</tr>”);
    29.                    sb.Append(“</thead>”);
    30.                    sb.Append(“<tbody>”);
    31.                    sb.Append(“<tr>”);
    32.                    sb.Append(“<td class=’service’>Design</td>”);
    33.                    sb.Append(“<td class=’desc’>Creating a recognizable design solution based on the company’s existing visual identity</td>”);
    34.                    sb.Append(“<td class=’unit’>$400.00</td>”);
    35.                    sb.Append(“<td class=’qty’>2</td>”);
    36.                    sb.Append(“<td class=’total’>$800.00</td>”);
    37.                    sb.Append(“</tr>”);
    38.                    sb.Append(“<tr>”);
    39.                    sb.Append(“<td colspan=’4′>SUBTOTAL</td>”);
    40.                    sb.Append(“<td class=’total’>$800.00</td>”);
    41.                    sb.Append(“</tr>”);
    42.                    sb.Append(“<tr>”);
    43.                    sb.Append(“<td colspan=’4′>TAX 25%</td>”);
    44.                    sb.Append(“<td class=’total’>$200.00</td>”);
    45.                    sb.Append(“</tr>”);
    46.                    sb.Append(“<tr>”);
    47.                    sb.Append(“<td colspan=’4′ class=’grand total’>GRAND TOTAL</td>”);
    48.                    sb.Append(“<td class=’grand total’>$1,000.00</td>”);
    49.                    sb.Append(“</tr>”);
    50.                    sb.Append(“</tbody>”);
    51.                    sb.Append(“</table>”);
    52.                    sb.Append(

      );

    53.                    sb.Append(
      NOTICE:

      );

    54.                    sb.Append(
      A finance charge of 1.5% will be made on unpaid balances after 30 days.

      );

    55.                    sb.Append(“</div>”);
    56.                    sb.Append(“</main>”);
    57.                    sb.Append(“<footer>”);
    58.                    sb.Append(“Invoice was created on a computer and is valid without the signature and seal.”);
    59.                    sb.Append(“</footer>”);

    I am using StringBuilder class for generating HTML string and pass to the parser for generating PDF. Before proceeding further add the following references.

    1. using iTextSharp.text;
    2. using iTextSharp.text.html.simpleparser;
    3. using iTextSharp.text.pdf;
    4. using System.Configuration;
    5. using System.IO;
    6. using System.Linq;
    7. using System.Net;
    8. using System.Net.Mail;
    9. using System.Text;
    10. using System.Web;
    Now let’s write the code for generating in-memory PDF from HTML string.
    1. StringReader sr = new StringReader(sb.ToString());
    2.                    Document pdfDoc = new Document(PageSize.A4, 10f, 10f, 10f, 0f);
    3.                    HTMLWorker htmlparser = new HTMLWorker(pdfDoc);
    4.                    using (MemoryStream memoryStream = new MemoryStream())
    5.                    {
    6.                        PdfWriter writer = PdfWriter.GetInstance(pdfDoc, memoryStream);
    7.                        pdfDoc.Open();
    8.                        htmlparser.Parse(sr);
    9.                        pdfDoc.Close();
    10.                        byte[] bytes = memoryStream.ToArray();
    11.                        memoryStream.Close();
    12.                    }

    Now let’s understand the Line of code. After building the string we can read from the string as we have passed the generated string.

    1. StringReader sr = new StringReader(sb.ToString());
    We are building the PDF document with default page size of A4 Page size.
    1. Document pdfDoc = new Document(PageSize.A4, 10f, 10f, 10f, 0f);

    Parse the HTML string using HTMLWorker of Itextsharp library,

    1. HTMLWorker htmlparser = new HTMLWorker(pdfDoc);

    Use the memory stream to reside the file in-memory.

    1. using (MemoryStream memoryStream = new MemoryStream())
    2.                     {
    3. }
    Now we get the PDF and memory stream to create the instance and write the document. Then first open the document, parse by the html worker and then after completing the work close the document (dispose off the resources) managing the resource properly.
    1. PdfWriter writer = PdfWriter.GetInstance(pdfDoc, memoryStream);
    2.                        pdfDoc.Open();
    3.                        htmlparser.Parse(sr);
    4.                        pdfDoc.Close();

    Now we add the created document to the memory stream and use the bytes of it as a in-memory reference to later attach to the email.

    1. byte[] bytes = memoryStream.ToArray();
    2.                memoryStream.Close();

    This is all about first step which will generate the PDF file and we will later use this as an attachment.

    First Output
    Now let’s proceed to the second step:
    Step 2:

    Email the Generated PDF File as an attachment. We will now use the Mail Message class to send email with in-memory generated PDF File.
    1. // From web.config
    2. string fromEmail = ConfigurationManager.AppSettings[“fromEmail”].ToString();            
    3.                         MailMessage mm = new MailMessage();
    4.                         mm.To.Add(“recipientaddress”);
    5.                         mm.From = new MailAddress(fromEmail);
    6.                         mm.Subject = “Online Request”;
    7.                         mm.Body = “Thanks for your time, Please find the attached invoice”;
    8.                         mm.Attachments.Add(new Attachment(new MemoryStream(bytes), “Invoice.pdf”));
    9.                         mm.IsBodyHtml = true;
    10.                         SmtpClient smtp = new SmtpClient();
    11.                         smtp.Host = ConfigurationManager.AppSettings[“SmtpServer”].ToString();
    12.                         smtp.EnableSsl = false;
    13.                         NetworkCredential NetworkCred = new NetworkCredential();
    14.                         NetworkCred.UserName = “info@email.com”;
    15.                         NetworkCred.Password = “email_password”;
    16.                         smtp.UseDefaultCredentials = true;
    17.                         smtp.Credentials = NetworkCred;
    18.                         smtp.Port = 25;
    19.                         smtp.Send(mm);
    You can use any email you receive from id by just authorizing the account i.e providing the network credentials. I have also use some application settings from web.config file and use here to get from there.
    1. <configuration>
    2.   <appSettings>
    3.       <add key=“fromEmail” value=“info@gmail.com”/>
    4.     <add key=“SmtpServer” value=“smtp.gmail.com”/>
    5.   </appSettings>
    6. </configuration>

    Final Output