Javascript variable in asp block code

Question

I have a lot of checkboxes that needs to execute the same javascript function when checked/unchecked. As parameter I enclose the control's server ID. My hope is to get the actual checkbox using this ID. The problem is that I need to find the client ID, but as expected I can't use my javascript variable myControlsServerID inside asp code blocks to get this ID. This is where I get stuck:

function show(myControlsServerID) {
   var checkbox = document.getElementById('<%= myControlsServerID.ClientID %>')
   //more omitted code
}

How can I get the clicked checkbox?

Ben Van Hees · Accepted Answer · 2013-07-23 12:00:45Z

1

Use jQuery to achieve this.

At document load initialize jQuery to listen to all checkboxes on your page. The moment you click on one of these, you can do whatever you want with it:

$(document).ready(function() {
    $("input:checkbox").click(function(e) {
        alert($(this).attr('id'));
    });
});

Download the latest jQuery version on http://jquery.com/download/

answered Jul 23, 2013 at 12:00

Ben Van Hees

3831 silver badge8 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Nurp Over a year ago

Nice solution! I don't even have to add the function to all checkboxes :) The only thing I still haven't figured out is how to get the "checked" status. It returns "undefined", while "type" and "id" show expected data. Will continue investigating. Thanks!

Ben Van Hees Over a year ago

Try $(this).is(":checked") - this will return true or false

Raghubar · Accepted Answer · 2013-07-23 12:00:51Z

1

chk.attributes.add("onclick","show('" + chk.ClientID + "')");


function show(myControlsServerID) {
   var checkbox = document.getElementById(myControlsServerID);  
 }

answered Jul 23, 2013 at 12:00

Raghubar

2,7981 gold badge23 silver badges31 bronze badges

1 Comment

Nurp Over a year ago

Doing it this way takes a lot of extra code, because I have to add this attribute to every checkbox and I have many of them. But next time, when I have only a few of them, this will be the my solution :)

Dhaval Marthak · Accepted Answer · 2013-07-23 12:07:33Z

1

You can do like this: use onchange="show(this);"

No need of doing these <%= myControlsServerID.ClientID %> of stuffs, simply call show() on your <asp:checkbox onchange='show(this);'>, it will automatically give you that clicked/checked element or we can say checkbox.

<input type="checkbox" value="chk1" id="chk001" onchange="show(this);"/>
<input type="checkbox" value="chk2" id="chk002" onchange="show(this);"/>
<input type="checkbox" value="chk3" id="chk003" onchange="show(this);"/>
<input type="checkbox" value="chk4" id="chk004" onchange="show(this);"/>

Javascript

function show(element) {
    var checkbox = element.id;
    alert("You have clicked " + checkbox);
    //more omitted code
}

Fiddle Demo

answered Jul 23, 2013 at 12:07

Dhaval Marthak

17.4k6 gold badges48 silver badges69 bronze badges

1 Comment

Nurp Over a year ago

I like this solution but your fiddle demo only shows how this works with the input control. I have noticed that an asp:checkbox renders as a span tag containing the checkbox. So "element" in your solution is in fact a span and I am unable to reach the checkbox anyway.

Collectives™ on Stack Overflow

Javascript variable in asp block code

3 Answers 3

2 Comments

1 Comment

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

2 Comments

1 Comment

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related