Question

I have added some web methods to my ASP.NET page like the following to enable AJAX calls using jQuery on the client side of my application:

public partial class MyPage : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        // Page load logic...
    }

    [WebMethod]
    [ScriptMethod(UseHttpGet = true, ResponseFormat = ResponseFormat.Json)]
    public static string MyWebMethod()
    {
        // web method logic...
    }
}

However, I noticed using the debugger that my web methods are being processed on a different AppDomain than my ASP.NET Page’s AppDomain, hence each one of them has its own set of static variables which is causing me some trouble.

So I would like to know if it’s somehow possible to host WebMethods (or a web-service) and an ASP.NET app on the same AppDomain, enabling both of them access to the same set of static variables?

Thanks in advance!

EDIT 1

I’m hosting my app on IIS 7.0

EDIT 2

As Jupaol’s answer clearly shows it is possible to host WebMethods and an ASP.NET page on the same appDomain, nevertheless here is what I found after running more tests:

If my jQuery.ajax call sets its URL like this:

$.ajax({
         url: "/MyFolder/MyPage.aspx/MyWebMethod",
         contentType: "application/json; charset=utf-8",
         success: AjaxSuccess,
         error: AjaxError
});

IIS creates two appDomains on my Web site (same web site key), one for the page request and another for the WebMethod request. Their FriendlyNames are showed below:

• “/LM/W3SVC/1/ROOT-6-129872125368848248” (WebMethod)
• “/LM/W3SVC/1/ROOT/WebApp-5-129872125273487796” (ASP.NET page request)

However, if the jQuery.ajax call URL is set like this:

$.ajax({
         url: "MyPage.aspx/MyWebMethod",
         contentType: "application/json; charset=utf-8",
         success: AjaxSuccess,
         error: AjaxError
});

Only one appDomain gets created to serve both requests:

• “/LM/W3SVC/1/ROOT/WebApp-7-129872126989518526”

Unfortunately I wasn’t able to find an explanation for this behaviour, and the only thing I can think of that may be related to this issue is that my web site uses https on some pages and not in others.

Answer 1

Are you sure that you are comparing the AppDomain’s ID???

I just made an experiment and they do belong to the same AppDomain

That could not always be true if you are explicitly creating AppDomains in code.

Example: (I just updated an old example I had, focus on the AppDomain.CurrentDomain.Id)

Code Behind

    protected void Page_Load(object sender, EventArgs e)
    {
        this.lblMessage.Text += "AppDomain ID: " + AppDomain.CurrentDomain.Id.ToString() + "<br/>";
    }

    [WebMethod]
    public static string Execute1()
    {
        JavaScriptSerializer j = new JavaScriptSerializer();
        string r = string.Empty;
        var o = Observable.Start(() =>
        {
            Thread.Sleep(2000);
            r = "My Name1: " + DateTime.Now.ToString() + " Background thread: " + Thread.CurrentThread.ManagedThreadId.ToString();
        }, Scheduler.NewThread);
        o.First();
        r += " Main thread: " + Thread.CurrentThread.ManagedThreadId.ToString();
        r += " AppDomain ID: " + AppDomain.CurrentDomain.Id.ToString();
        r = j.Serialize(new { res = r });
        return r;
    }

Output