Displaying jquery progressbar with ajax call on a modal dialog

Working on a website of which one of the requirement is to display a progress bar while completing an ajax call. Yes this is a simple and straight forward requirement and lets look to the details of how to implement it.

1. Create a web service

2. Using jQuery do the following :-
2.1 Show modal dialog box
2.2 show progress bar on the modal dialog box as 0% completed
2.3 Make an ajax call (estimated time of 5 mins)
3. While ajax call is processing make another ajax call to the web service to find the percentage completed and do this using set interval (or) using jquery count down plugin

Now that we have the design aspect, lets start implementing this.

At first an ajax call (ProcessRequest() - webservice method) is made and after 10 secs another ajax call ProcessStatus() - webservice method) is made to retrieve the percentage completed.

AjaxWebService.asmx

[WebMethod, ScriptMethod(ResponseFormat = ResponseFormat.Json)]
public string ProcessRequest()
{
   return AjaxData.AjaxProcess();
}

[WebMethod, ScriptMethod(ResponseFormat = ResponseFormat.Json)]
public int ProcessStatus()
{
   return AjaxData.AjaxStatus();
}

AjaxData.cs

public class AjaxData
{
    private static int status = 0;

 public AjaxData()
 {
        status = 0;
 }

    public static string AjaxProcess()
    {
        string retValue = "Started";
        status = 0;
        for(int i=1;i<=100;i++)
        {
            System.Threading.Thread.Sleep(100);
            status++;
        }

        retValue = "Completed Successfully !";
        return retValue;
    }

    public static int AjaxStatus()
    {
        return status;
    }

}

default.aspx (script)

The complete project source code is available on Codeplex

“Physics is the universe’s operating system.” – Steven R Garman

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Unable to uninstall: assembly is required by one or more applications

Un-installing from GAC can be done in various methods such as :-

1. Using windows explorer goto C:\Windows\assembly
2. Locate the assembly
3. use delete button (or) right click -> Uninstall

Alternate method is

1. Goto Visual Studio Command prompt
2. type gacutil /u Me.Test.Assembly

If both of these doesn't work then the assembly is used by some of the component. Ok now that you have known that assembly has a dependency but still you want to delete. This might occur in a scenario where in you want to update the assembly with the new version not by having side by side but having only latest version. This can be achieved by clearing some of the entries in the registry. The entry for the assembly can be in one of these two locations:-


HKEY_CURRENT_USER\Software\Microsoft\Installer\Assemblies\Global
(or)
HKEY_LOCAL_MACHINE\Software\Classes\Installer\Assemblies\Global


Locate the entry related to your assembly and delete it, this should remove the dependency. Now just go and uninstall from GAC using either of the two methods above.


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- Russell Davies

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Sys._ScriptLoader is null or not an object

Working on a website and have got following error :-

"Sys._ScriptLoader is null or not an object"

Have been using the methodology of downloading multiple javascript files after the visible content. When combine script is enabled the above error is displayed.

The reason for this error being the definition of the following function :-

$type = Sys._ScriptLoader = function _ScriptLoader() {

has not been loaded so need to exclude respective scriptResource.axd during combine scripts mode. Hope this might help to fix some of the issues.

“Real knowledge is to know the extent of one’s ignorance.”
– Confucius

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Unable to get readonly textbox value from server side ASP.NET

Unable to get textbox value from server side is not a bug in ASP.NET but is a feature. Textbox value cannot be read from code behind if it is readonly as per MSDN .

But the value can be read using the following syntax :

txtFirstName.Text = Request[txtFirstName.UniqueID];


“The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge.”
– Stephen Hawking

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