Call Javascript Function from Code Behind in Asp.net C#

9 comments on “Call Javascript Function from Code Behind in Asp.net C#”

1. 

   Brennan Young March 22, 2017 at 11:54 am

   Very useful, thanks.

   Just want to mention that this will fail if your code behind (i.e. Response) is returning a download instead of an html page for display in the browser. Obvious perhaps. But it wasn’t to me at first.

   Reply
   • 

     Satinder singh April 6, 2017 at 6:16 am

     Hello Brennan Young,
     Sorry i didn’t get your point?

     Reply
2. 

   Pratik January 31, 2017 at 6:31 am

   ScriptManager.RegisterStartupScript(Me, [GetType](), “Javascript”, “javascript:Sch3Collapse(); “, True)

   does not work on postback

   Reply
   • 

     Satinder singh January 31, 2017 at 10:23 am

     Hi Pratik,
     The above code worked for me, that is I able to call javascript function whenever I clicked asp.net button control. Am not sure how you used above code. But if you have added update panel from ajax toolkit, then you need to add below script at the bottom of your Web page ( .aspx page)

      
     <script type="text/javascript">
        Sys.WebForms.PageRequestManager.getInstance().add_endRequest(InIEvent);
     </script>
     

     ---

     <script>
     function InIEvent(){
       
      function fn_1(){
         // client side function here
       }
      
     function fn_2(){
         // client side function here
       }
     
     }
     </script>

     Reply
3. 

   John Craig January 11, 2017 at 4:51 am

   Thanks! Works perfectly

   Reply
   • 

     Satinder singh January 16, 2017 at 10:28 am

     Hi John
     Am glad this helps you

     Reply
4. 

   Domingo Morales October 12, 2016 at 3:48 am

   Thank you.

   ??how to pass arguments to the javascript function being called.

   ??returning a result from the javascript function.

   Thank you.

   Reply
   • 

     Satinder singh October 13, 2016 at 6:41 am

     Hello Domingo,
     
     For passing arguments / parameters you can simply pass value to the JS function from code-behind C#
     
     For example :
     Code behind:
     string strParamter = "Hello World test";
ClientScript.RegisterStartupScript(GetType(), "Javascript", "javascript:helloWorld('"+strParamter+"'); ", true);

     ---

     Client side (.aspx):
     function helloWorld(data) {
alert(data);
}

     Reply
5. 

   Mick May 19, 2015 at 11:30 am

   Thanks i was finding it difficult to get javascript function from .cs page .

   Reply