Call ASP.NET function from JavaScript?

Question

I\'m writing a web page in ASP.NET. I have some JavaScript code, and I have a submit button with a click event.

Is it possible to call a method I created in ASP with

Answer 1

The Microsoft AJAX library will accomplish this. You could also create your own solution that involves using AJAX to call your own aspx (as basically) script files to run .NET functions.

This is the library called AjaxPro which was written an MVP named Michael Schwarz. This was library was not written by Microsoft.

I have used AjaxPro extensively, and it is a very nice library, that I would recommend for simple callbacks to the server. It does function well with the Microsoft version of Ajax with no issues. However, I would note, with how easy Microsoft has made Ajax, I would only use it if really necessary. It takes a lot of JavaScript to do some really complicated functionality that you get from Microsoft by just dropping it into an update panel.

Answer 2

If the __doPostBack function is not generated on the page you need to insert a control to force it like this:

<asp:Button ID="btnJavascript" runat="server" UseSubmitBehavior="false" />

Answer 3

Regarding:

var button = document.getElementById(/* Button client id */);

button.click();

It should be like:

var button = document.getElementById('<%=formID.ClientID%>');

Where formID is the ASP.NET control ID in the .aspx file.

Answer 4

This reply works like a breeze for me thanks cross browser:

The __doPostBack() method works well.

Another solution (very hackish) is to simply add an invisible ASP button in your markup and click it with a JavaScript method.

<div style="display: none;"> 
    <asp:Button runat="server" ... OnClick="ButtonClickHandlerMethod" /> 
</div> 

From your JavaScript, retrieve the reference to the button using its ClientID and then call the .Click() method on it:

var button = document.getElementByID(/* button client id */); 

button.Click(); 

Blockquote

Answer 5

The simplest and best way to achieve this is to use the onmouseup() JavaScript event rather than onclick()

That way you will fire JavaScript after you click and it won't interfere with the ASP OnClick() event.

Answer 6

The __doPostBack() method works well.

Another solution (very hackish) is to simply add an invisible ASP button in your markup and click it with a JavaScript method.

<div style="display: none;">
   <asp:Button runat="server" ... OnClick="ButtonClickHandlerMethod" />
</div>

From your JavaScript, retrieve the reference to the button using its ClientID and then call the .click() method on it.

var button = document.getElementById(/* button client id */);

button.click();