List Box Validation

[veenna]

hi,

Following function i am using for validating list box. In list box user can select only 5 item .

 function Validate()
    {
          var lblCount=0;
          var lbGenre = document.getElementById('<% Response.Write(lstbox.UniqueID); %>');
           for(var x = 0; x < lbGenre.options.length; x++)
            {
                 if(lbGenre.options[x].selected)
                 {
                    lblCount+=1;
                 }
            }
            if(lblCount > 5)
            {              
              alert("maximum five!");  
              return false;
            }
    }

That is working fine. i want to how to unselect the six item selected from list box?


regards
veena

[veenna]

Can any one please tell me How to unselect one item from list box?

Regards
Veena

[RamananKalirajan]

Hi Veena,
Its difficult to unselect a particular option in multiselect.

Thanks and Regards
Ramanan Kalirajan

[Dormilich]

Its difficult to unselect a particular option in multiselect.

doesn’t the usual ctrl+click work? (untested)

[RamananKalirajan]

She is asking about unselcting through JS.. It can be done using document.getEle mentById('sampl eSelect').optio ns[selectedIndex].selected="fals e", this will work in Mozilla but not in IE. This is a problem.

Thanks and Regards
Ramanan Kalirajan

[ivosilva]

Hello, veenna!

I have tested the following code in IE8, Firefox 3.5 and Chrome 3.0 and it seems to work fine (I have no previous versions of IE installed to test it).

function validate() {
			var max = 2;
			var lblCount = 0;
			var lbGenre = document.getElementById('<% Response.Write(lstbox.UniqueID); %>');
			
			for(var x = 0; x < lbGenre.options.length; x++) {
			
				if(lbGenre.options[x].selected) {
				
					lblCount++;
					
					if(lblCount > max) {
						lbGenre.options[x].selected = false;
					}
				}
			}
			
			if(lblCount > max) {
				alert("You can only select a maximum of " + max + " options!");
				return false;
			}
		}

Best regards

[RamananKalirajan]

In IE6, it wont be working yaar...

Thanks and Regards
Ramanan Kalirajan

[ivosilva]

Hello, RamananKaliraja n!

I've just tested it under IE6 and it works ok.

Have you tested my code using IE6?

Best regards!