ASP.NET AJAX Discussion and Suggestions

Re: Ajax and Response.Write

Mr. Javaman — Wed, 05 Nov 2008 04:58:13 GMT

Okay so this is a prohibited thing AJAX and Response.Write.... So shouldn't any control in an update panel be updateable? In Java, labels can utilize HTML, but not ASP:Labels, so if I have formatted HTML that I want to use how do I get it out? Response.Write will take a string of HTML and do a beautiful job EXCEPT when in an UPDATE Panel.

BTW... This problem has been known since 2002 how long does it take to fix and or realize this is just a dumb restriction.

Re: Ajax and Response.Write

prgoncalves — Fri, 10 Oct 2008 10:16:09 GMT

I had the same problem when passing values to pages beacaus I was creating a form to submit with Response.Write(), that had problem with ajax.

The solution I found is using a dinamic form created from javascript, based on the example:

http://en.allexperts.com/q/Javascript-1520/create-form-submit-fly.htm

I use the next function to pass values to another page. Here I use the scripts in the link above.

public static void submitValues(System.Collections.Specialized.NameValueCollection dados, string url)
{
Page currentPage = (Page)HttpContext.Current.CurrentHandler;
ScriptManager currentScriptManager = ScriptManager.GetCurrent(currentPage);

StringBuilder sb = new StringBuilder();
sb.Append("var submitForm = getNewSubmitForm();");

foreach (string key in dados.Keys)
{
    sb.Append(string.Format("createNewFormElement(submitForm, '{0}', '{1}');", key, dados[key]));
}
sb.Append(string.Format("submitForm.action = '{0}';", url));
sb.Append("submitForm.submit();");
string scriptPost = sb.ToString();

if (currentScriptManager != null && currentScriptManager.IsInAsyncPostBack)
{
    #region Came from AJAX request
    ScriptManager.RegisterStartupScript(currentPage, typeof(string), "submitAjax", scriptPost, true);
   #endregion
}
else
{
   #region Came from normal request
   currentPage.ClientScript.RegisterStartupScript(typeof(string), "submitNoAjax", scriptPost, true);
   #endregion
}
}

Re: Ajax and Response.Write

gkopparam — Mon, 31 Mar 2008 13:40:28 GMT

How will i be able use registerStratup script when i want to write back a new form to the client and then, do a submit of that for i just created.

but when i use response.write in normal pages the above works absolutely fine. but in AJAX enabled web pages it gives me the 500 error .

thanks

Re: Ajax and Response.Write

js2004 — Fri, 09 Mar 2007 13:28:54 GMT

Steve Marx:

The response from the server from an async postback has to have a particular format so that the AJAX Library running in the browser can parse it. Response.Write changes the format of the response, making it unparsable. That's why Response.Write is incompatible with asynchronous postbacks.

For examples such as the one in this thread, ScriptManager.RegisterStartupScript(...) is usually what you need.

Yours Truly,
Steve Marx
Microsquish Weenie

Ok. Thank you Steve.

jsmith

Re: Ajax and Response.Write

Steve Marx — Thu, 08 Mar 2007 00:46:42 GMT

The response from the server from an async postback has to have a particular format so that the AJAX Library running in the browser can parse it. Response.Write changes the format of the response, making it unparsable. That's why Response.Write is incompatible with asynchronous postbacks.

For examples such as the one in this thread, ScriptManager.RegisterStartupScript(...) is usually what you need.

Yours Truly,
Steve Marx
Microsquish Weenie

Re: Ajax and Response.Write

fcedotal — Wed, 07 Mar 2007 23:12:01 GMT

I think what is happening is this: (but won't bet my life on it!)

When you put something in your code-behind page that renders javascript, Ajax is controlling javascript at this point and it won't let anything else get rendered, UNLESS you register the script in your code behind page.

Registering the script lets Ajax know that javascript is being rendered, so Ajax know what to do with it.

I wish one of the Microsquish weenies would respond to this.

fcedotal

Re: Ajax and Response.Write

Lovely — Wed, 07 Mar 2007 22:31:13 GMT

You can use this way:

 protected void Menu1_MenuItemClick1(object sender, MenuEventArgs e)
    {
        ScriptManager.RegisterStartupScript(this, this.GetType(), "key", "confirm('Are you sure you want to delete?');", true);
    }

Re: Ajax and Response.Write

js2004 — Wed, 07 Mar 2007 21:50:51 GMT

paul.vencill:

It's not a problem; I've done it. Can you post code?

Have you used Ajax.net v1.0 and Response.Write together?

Regards,

jsmith

Re: Ajax and Response.Write

js2004 — Wed, 07 Mar 2007 21:45:34 GMT

That is right I can use ScriptManger.RegisterStartupScript(or RegisterClientScriptBlock). But that script gets written in page when it is loaded.

But that does not meet requirements if I have to dynamically write javascript during an ajax method call.

Consider the case: Trying to use Ajax to handle the OnMenuItemClick event of Asp:Menu, I need to warn users through a dialog box that if they navigate away from the page their data will be lost. Easy solution will be to do a Response.Write(confirm) in the event. But because of the inability of Ajax and Response.Write to work together I had to do a lot of twists to get the same effect. Even if I write javascript to a literal control and add it to page at run time I get the same error. I am not sure if I write javascript to a label it will work.

That is why I was wondering if there is a way to use Ajax and Response.Write at the same time in a page.

Best Regards,

jsmith

Re: Ajax and Response.Write

Lovely — Wed, 07 Mar 2007 13:04:21 GMT

js2004:
Here is a discussion of the error:

http://dotnetdebug.net/2006/12/28/syswebformspagerequestmanagerparsererrorexception/

But I cannot use the solution discussed here.

jsmith

Response.Write not support with ASP.NET AJAX . You can use Scriptmanager mothod like the post before. Or put your text in a Lable,"This suggestion from the blog you put it up". Regards.

Re: Ajax and Response.Write

Lovely — Wed, 07 Mar 2007 13:03:32 GMT

js2004:
Here is a discussion of the error:

http://dotnetdebug.net/2006/12/28/syswebformspagerequestmanagerparsererrorexception/

But I cannot use the solution discussed here.

jsmith

Response.Write not support with ASP.NET AJAX . You can use Scriptmanager mothod like the post before. Or put your text in a Lable,"This suggestion from the blog you put it up". Regards.

Re: Ajax and Response.Write

js2004 — Wed, 07 Mar 2007 02:25:51 GMT

Here is a discussion of the error:

http://dotnetdebug.net/2006/12/28/syswebformspagerequestmanagerparsererrorexception/

But I cannot use the solution discussed here.

jsmith

Re: Ajax and Response.Write

fcedotal — Tue, 06 Mar 2007 18:47:37 GMT

Thanks, it is working now. This is what the new code looks like:

MakeModelInputTable()
ScriptManager.RegisterStartupScript(updAgitData, updAgitData.GetType, "key", "<script language='javascript'>showModalDialog('SpargerChooser.aspx', null,'status:no;dialogWidth:400px;dialogHeight:650px;dialogHide:false;help:no;scroll:no');</script>", False)

Re: Ajax and Response.Write

Lovely — Tue, 06 Mar 2007 17:03:38 GMT

You can use the RegisterStartupScript method in this POST,

and showModalDialog in the same way.

Regards.

Re: Ajax and Response.Write

fcedotal — Tue, 06 Mar 2007 16:48:07 GMT

I am having the same problem displaying a modla dialog. It used to work, but when the panel that contains the button that ran the code to display the modal dialog is wrapped in an update panel, it quit working.

Private Sub btnShowSpargerParms_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnShowSpargerParms.Click
        MakeModelInputTable()
        Response.Write("<script language='javascript'>showModalDialog('SpargerChooser.aspx', null,'status:no;dialogWidth:400px;dialogHeight:650px;dialogHide:false;help:no;scroll:no');</script>")
    End Sub

MakeModelInputTable gets some parameters from the current page, puts them into a session variable, then I display the modal dialog which does some calculations in the pageload using the parameters in the session variable, then displays the results on the modal dialog.