Solved

Find the last checkbox checked

Posted on 2008-06-13
7
314 Views
Last Modified: 2008-06-17
I have a group of 3 checkbox. The user can click on any check box,but I want to track the last checkbox checked. The user can check checkbox 1,3 and 2. I want to do this on a button click event. Then I need the id 2. Izt possible in javascript.
0
Comment
Question by:ip32
7 Comments
 
LVL 41

Expert Comment

by:HonorGod
Comment Utility
If they all have the same "name" attribute, this is easy.

  var group = document.getElementsByName( "groupName" );
  var last = null;
  for ( var i = 0; i < group.length; i++ ) {
    if ( group[ i ].checked ) {
      last = group[ i ];
    }
  }
  if ( last ) {
    alert( 'last checked: ' + last.value );
  }
0
 
LVL 22

Expert Comment

by:prairiedog
Comment Utility
Very interesting question. What if the user does this:
Checked 1, 3, and 2, then unchecked 2. What Id do you need?
0
 
LVL 33

Expert Comment

by:raterus
Comment Utility
I did something similar a long time ago.  I ended up appending to a hidden field an indicator that the box was checked.  If they unchecked the box, I searched the hidden field and removed the indicator.  On a postback, I parsed the list and determined the check order.
0
How your wiki can always stay up-to-date

Quip doubles as a “living” wiki and a project management tool that evolves with your organization. As you finish projects in Quip, the work remains, easily accessible to all team members, new and old.
- Increase transparency
- Onboard new hires faster
- Access from mobile/offline

 
LVL 41

Accepted Solution

by:
HonorGod earned 250 total points
Comment Utility
Sorry for my incomplete understanding of the issue.

As suggested, I would have a field that keeps a list of the checked boxes, in stack fashion, and remove the instance from the list when the item was unchecked.

For example:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">

<html>

<head>

<title> Last checked </title>

<script type='text/javascript'>

  var checked = [];

  function check( id ) {

    var ele = document.getElementById( id );

    if ( ele && ele.checked ) {

      checked.push( id );

    } else {

      for ( var i = 0; i < checked.length; i++ ) {

        if ( checked[ i ] == id ) {

          checked.splice( i, 1 );

          break;

        }

      }

    }

    var debug = document.getElementById( 'debug' );

    if ( debug ) {

      var copy = checked;

      copy.reverse();

      debug.innerHTML = 'checked order: ' + copy.toString();

    }

  }

</script>

</head>

<body>

<table border='1'>

  <tbody>

    <tr>

      <td>Checkbox 0:<input type='checkbox' id='cb0' onclick='check(this.id)'></td>

    </tr>

    <tr>

      <td>Checkbox 1:<input type='checkbox' id='cb1' onclick='check(this.id)'></td>

    </tr>

    <tr>

      <td>Checkbox 2:<input type='checkbox' id='cb2' onclick='check(this.id)'></td>

    </tr>

    <tr>

      <td>Checkbox 3:<input type='checkbox' id='cb3' onclick='check(this.id)'></td>

    </tr>

    <tr>

      <td>Checkbox 4:<input type='checkbox' id='cb4' onclick='check(this.id)'></td>

    </tr>

    <tr>

      <td>Checkbox 5:<input type='checkbox' id='cb5' onclick='check(this.id)'></td>

    </tr>

    <tr>

      <td>Checkbox 6:<input type='checkbox' id='cb6' onclick='check(this.id)'></td>

    </tr>

    <tr>

      <td>Checkbox 7:<input type='checkbox' id='cb7' onclick='check(this.id)'></td>

    </tr>

    <tr>

      <td>Checkbox 8:<input type='checkbox' id='cb8' onclick='check(this.id)'></td>

    </tr>

    <tr>

      <td>Checkbox 9:<input type='checkbox' id='cb9' onclick='check(this.id)'></td>

    </tr>

  </tbody>

</table>

<div id='debug'></div>

</body>

</html>

Open in new window

0
 

Author Comment

by:ip32
Comment Utility
Excellent. Izt possible to acheive this in asp.net since there is no click event. I do not want to go to the code behind and give the click event..
0
 
LVL 41

Expert Comment

by:HonorGod
Comment Utility
probably, but unfortunately, I know nothing about ASP.NET.
I saw the question because of the "javascript" tag...
0
 
LVL 41

Expert Comment

by:HonorGod
Comment Utility
Hopefully you were able to use the information to help you resolve the issue
using ASP.  Thanks for the grade & points.

Good luck & have a great day
0

Featured Post

Better Security Awareness With Threat Intelligence

See how one of the leading financial services organizations uses Recorded Future as part of a holistic threat intelligence program to promote security awareness and proactively and efficiently identify threats.

Join & Write a Comment

Sometimes in DotNetNuke module development you want to swap controls within the same module definition.  In doing this DNN (somewhat annoyingly) swaps the Skin and Container definitions to the default admin selections.  To get around this you need t…
ASP.Net to Oracle Connectivity Recently I had to develop an ASP.NET application connecting to an Oracle database.As I am doing it first time ,I had to solve several problems. This article will help to such developers  to develop an ASP.NET client…
Excel styles will make formatting consistent and let you apply and change formatting faster. In this tutorial, you'll learn how to use Excel's built-in styles, how to modify styles, and how to create your own. You'll also learn how to use your custo…
This demo shows you how to set up the containerized NetScaler CPX with NetScaler Management and Analytics System in a non-routable Mesos/Marathon environment for use with Micro-Services applications.

763 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

11 Experts available now in Live!

Get 1:1 Help Now