从C＃和Asp.Net背后的代码调用JavaScript

Question

Am unable to understand why Cannot the below javascript code is not called from code behind

I have a simple javascript block like this

  function callsCox(res) {
    alert(res);
   }

From my code behind :

 ....
 string res="COX23";
 string script = String.Format("callsCox({0})", res);
 this.Page.ClientScript.RegisterStartupScript(this.GetType(), "Cox",script,true);

Am I missing anything? There aren't any exceptions or errors.

Answer 1

Page.ClientScript.RegisterStartupScript looks OK to me (might have missed something). Things to try

1. Add apostrophes to the call - it's coming through as an object. Try as a string

   string script = String.Format("callsCox('{0}')", res);

2. Is the string script Page.ClientScript.RegisterStartupScript being called after an update panel partial postback. That could effect it

3. I have know functions not been found if they are in the same page. Try moving to an external js file. Don't asked me why this has resolved issues but it has a couple of times in the past for me.

4. Just for debug purposes take the function out of the equation all together, Try to get the alert working like this. It will at least isolate the problem if it does work

   this.Page.ClientScript.RegisterStartupScript(this.GetType(), "Cox","alert('Does this work?')",true);

5. View the source of the page. Is the function even written into the page (or alert from point 4). It should be. If you put a breakpoint on the this.Page.ClientScript.RegisterStartupScript method is it being hit? Seems like it might not be.

Apologies for not giving you a 'hey this is the solution' type of answer. I've had stuff like this in the past and I've found it a matter of stripping things down until the problem has been isolated. Someone else may be able to spot an immediate problem of course. Good luck.

Answer 2

This works for me:

public static void ShowAlert(Page page, String message)
{
    String Output;
    Output = String.Format("alert('{0}');",message);
    page.ClientScript.RegisterStartupScript(page.GetType(), "Key", Output, true);
}