Category Archives: VB.NET

[C# and VB.Net] How to close a form after confirmation in Winforms

How to close a form in c#  after confirming



You can put the following code in any button


          if (MessageBox.Show("Are you sure you want to exit?", "Close Application", MessageBoxButtons.YesNo) == DialogResult.Yes)


In VB.NET you can use the following code


 If MsgBox("Are you sure you want to close", MsgBoxStyle.YesNo, "Close Application") = MsgBoxResult.Yes Then

        End If

Could not load file or assembly ‘System.Web.Http.WebHost, Version=, Culture=neutral, PublicKeyToken=31bf3856ad364e35′ or one of its dependencies. The system cannot find the file specified.

Could not load file or assembly ‘System.Web.Http.WebHost, Version=, Culture=neutral, PublicKeyToken=31bf3856ad364e35′ or one of its dependencies. The system cannot find the file specified.



I had a Visual Studio 2013 project using MVC4. The application was working fine in my local machine. But when I deployed the application using FileSystem( in this method all the files for the project gets copied to a folder on your local machine, then you can copy all these files to your webhost and your application should start working.)


I got the following error when I deployed the application using this method.

Could not load file or assembly ‘System.Web.Http.WebHost, Version=, Culture=neutral, PublicKeyToken=31bf3856ad364e35′ or one of its dependencies. The system cannot find the file specified.


How to Fix it?

I searched on the web for  some time to get the answer and in the end I discovered that the System.Web.HTTP.WebHost.DLL file was not being copied to my published folder and hence the error.

1. Go to the solution Explorer in Visual Studio

2. Go to the References

3. Right Mouse Click on the System.Web.HTTP.WebHost entry  to check its prooperties and I found that COPY LOCAL proeprty was set to false and hence the file was not being copied to my published folder.

4. I changed the COPY LOCAL to true and then the file gets copied to  my published folder and gets deployed correctly.


How to render @html.actionlink as a button in MVC in Razor

How to render  @HTML.Actionlink  in MVC and using it as a button

Background of @HTML.ACTIONLINK in MVC

The easiest way to render an HTML link in is to use the HTML.ActionLink() helper.

With MVC, the Html.ActionLink() does not link to a view. It creates a link to a controller action.

Razor Syntax:

@Html.ActionLink(“About this Website”, “About”)

ASP Syntax:

<%=Html.ActionLink(“About this Website”, “About”)%>

The first parameter is the link text, and the second parameter is the name of the controller action.

The Html.ActionLink() helper above, outputs the following HTML:

<a href=”/Home/About”>About this Website</a>



When using  @html.actionlink it normally renders it like a hyperlink. But there is a simple way to render it as a button.


Simple example of  @HTML.Actionlink



and it will render it as a  Hyperlink



How to render  @HTML.Actionlink as a button


I am using Boostrap so I have the CSS class called “btn” available. Otherwise you can use your own CSS which can create a button


 Here is your Answer below

C# Syntax

@Html.ActionLink("Register", "Register" ,null,  new { @class = "btn" })


VB.NET Syntax

@Html.ActionLink("Register", "Register" ,null,  new  with {.class = "btn" })   

the null is for the Routevalues ( in the example we are using any route values hence null)


Hope this helps you

VB.NET – You must call the “WebSecurity.InitializeDatabaseConnection” method before you call any other method of the “WebSecurity” class.

Problem description:

If you are getting the error while running your MVC4 application in VB.NET

You must call the “WebSecurity.InitializeDatabaseConnection” method before you call any other method of the “WebSecurity” class.


Add the following line in the GLOBAL.ASX



Ensure that you are using the correct connection string and other information as per your own application as  shown in the highlighted line above.

VB.NET – ASP NET MVC Area routing/multiple routes issue in VB.NET

Scenario: If you have two controllers with the same name in different areas, then you would end up with errors as shown below, while there are numerous examples available on the web but it took me a while to figure out the correct solution for VB.

Hope it help you and saves you time.

Problem Description

I have a HOME controller in my MVC4 application and then I created a new AREA called SUPERADMIN. I then created a HOME controller in that area as well.I received the following error.

Error with duplicate controller names







1. Fix the Route.Config in your MVC4 project under APP_Start folder. See the yellow coloured text,


vbnull is for constraints( so we are not adding special constraints

the next one “RealEstateVB” is the namespace , RealEstateVB is the name of my application and is taken as the default namespace.

Adding Namespace in ROUTE

2. Now Go to your AREA. I had an area called SUPERADMIN.

See the highlighted text. You have to define the namespace. eg. I have used “RealEstateVB.Areas.Superadmin for my SuperAdmin area.

Also make a note how I have added superadmin in front of the /{controller}/{action}/{id}

Adding namespace in Area



This should get your project going without any errors. For each area you have you will need to fix the xxxAreaRegistration.vb file as described in the above step(2)

Role based Authorization in MVC4 using VB.NET

Here is a simple way to do the role based Authorization in your MVC4 Controllers using VB.NET

IF you have a role called Client then simply add the following text on top of your each ActionResult( which displays the view)



See the following example. The Index View has been restricted and can only be viewed by someone in the Client role.

        Function Index() As ActionResult
            Return View(db.Purchasers.ToList())
        End Function

Password protect complete MVC4 site in VB.NET

If you want to password protect some pages on your MVC4 site using the Forms Authentication then it is best to to protect the whole site and then selectively allow Anonymous Access to the pages which are to be shown to every visitor.
authentication in MVC4

Open the FilterConfig.VB file and add the line

filters.Add(New AuthorizeAttribute)   in it


Once you run your application you would see that all the pages of your website are now protected, the users have to register before they can access.


Imports System.Web
 Imports System.Web.Mvc
Public Class FilterConfig
 Public Shared Sub RegisterGlobalFilters(ByVal filters As GlobalFilterCollection)
 filters.Add(New HandleErrorAttribute())
 filters.Add(New AuthorizeAttribute)
 End Sub
 End Class


If you need to allow some pages for anonymous view then add the following decoration.

<AllowAnonymouse()> on each page which you want to open up for anonymous access.


    Function Index() As ActionResult
        ViewData("Message") = "Modify this template to jump-start your ASP.NET MVC application."
        Dim rep As New RepositoryRealEstate

        ViewBag.AgentCount = rep.GetAgentsCount
        ViewBag.ProperyCount = rep.GetPropertyCount
        ViewBag.VendorCount = rep.getvendorcount
        Return View()
    End Function

How to create a GUID in VB.NET

Here is a small function to return the GUID.

GUID stands for Globally Unique Identifiers. GUIDs are 128-bit globally unique identifiers and they are generated automatically based on close to two zillion frequently varying factors.
It has extremely low possibility that a generated GUID would equal to another GUID.

Function GenerateGUID() as string
return System.Guid.NewGuid.ToString()
End function

How to use Application Settings in Windows Forms using VB.NET

Learn how to use Applications Settings in Visual Studio 2013 Winform project in VB.NET


Here is a simple way of storing applications settings.


Step 1

In your Visual Studio Project open the settings.

Winform Settings
Winform Settings

Step 2

When you click on the Settings as shown in Step 1, you would get the following screen.

You can create your settings as shown below by providing your customised values in the Value column as shown below



Step 3


Here is how you will use those values in your project . Learn how to use settings in winform