Migrating old source code of Visual Studio 2010 to Visual Studio 2012

Step 1: Enable nuget restore. Find and click on Project then find and click enable nuget restore.

Step 2: Manage nuget packages and install entityframework and ajaxcontroltoolkit.

Step 3. Download and install ajaxcontroltoolkit 4.5.

Step 4: Click on Toolbox then choose item, browse and find AjaxControlToolkit.dll version 4.5.

Step 5: Add reference to all dll that you need in your project and can be found here, C:\Program Files (x86)\Microsoft Visual Studio 11.0\. For example,
Microsoft.ReportViewer.Common
Microsoft.ReportViewer.WebForms
System.Data.Entity

Step 6: Select a page to set as start page.

Step 7: Replace the following align or valign with vertical and text-align respectively.
Refer to this link,
 My other blog

Step 8: There are items to change in css 3 from css 1, like cursor:hand to cursor:pointer.
Browser Support
To align right,
click here

Step 9: To deploy or publish the web application. Please refer to the link below,
Reference 1
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Reference 5

Step 10: Check for any missing dll. If you cannot find some of them, refer to this link below,
Reference 1

Step 11: To position two column table in the center at the top menu, add this css to menu.css file. .wrapper { position: absolute; left: 50%; margin-left: -70px; } the idea came from this link,
Align Contents

Step 12: When you wish to insert a image as a background, insert into a css file, this css below, background: url(../Images/ERRPAGE.png) center no-repeat;

width: 100%;
height: 100%;
position: absolute;
top: 0;
left: 0;
background-size: auto auto;

Reference used:
background size
vertical centering

Step 13: If you receive an error message "Unable to evaluate expression because the code is optimized or a native frame is on top of the call stack", apply this code before your redirect to error page like this code below,
if (ex.Message.StartsWith("Thread") == false)
{
Session["ErrorMessage"] = ex.Message;
Response.Redirect("~/Forms/Error.aspx", false);
}
Reference used for step 13,
Reference used

Step 14: to change the color of the scrollbar of a panel, use the link below,
Bar color
CSS Tutorial
There is no direct way of changing color of scrollbar in a treeview control unless you create new custom treeview control.

Step 15: In case you have this javascript error message "0x800a139e - JavaScript runtime error: Sys.WebForms.PageRequestManagerParserErrorException: The message received from the server could not be parsed.", you can insert this meta tag in the master page,

 <meta http-equiv="X-UA-Compatible" content="IE=9" />

Step 16: To enable clicking on word displayed to expand the tree. Set the property SelectAction to Expand. To display the treeview in unexpanded format. Set the property Expanded to False.

<asp:TreeNode Text="Transaction" Value="Process" ImageUrl="~/Images/folder.png" Expanded="false" SelectAction="Expand" >

Step 17: To remove the default arrows that appear in the ASP.NET Menu Control. Set the StaticEnableDefaultPopOutImage property to False. This property is responsible for the default arrows that appear in the ASP.NET Menu control. To remove the default arrows that appear in the ASP.NET menu items. Set the DynamicEnableDefaultPopOutImage property to False. This property gets or sets a value indicating whether the built-in image that indicates that a dynamic menu item has a submenu is displayed.

Reference used for step 17:
Reference for DynamicEnableDefaultPopOutImage
Reference for StaticEnableDefaultPopOutImage
Another Reference for StaticEnableDefaultPopOutImage

Step 18: Fixing the displaying of rdlc inside a report viewer 2012 using IIS 7. Please refer to this link to add handler mappings at iis.

Step 19: To display Elmah.axd, allow remote access by setting allowRemoteAccess from false to true at web config file. And add a file extension to allow . Find and click Request Filtering. Find and click Allow file name extension link. Type in .axd at File name extension and then click OK.

Step 20: To insert space between menu and submenu, put some value at DynamicMenuItemStyle-HorizontalPadding  property.
Reference used for step 20

Migrating from Visual Studio 2010 to Visual Studio 2012
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