Asp.net Textbox onChange

You can use javascript . . . also AJAX might take care of the postback issue for you as well.

@ged325..
AJAX takes d process to server side.. but it takes only partial data.

@gogetsome..
u ve to use javascript or jquery for the same which are client side scripting...
so basically u ve to use client side scripting...

Very well you can go with javascript , thats pretty simple instead of making a post back to perform this simple operation .

Thanks Guys! Yes... I want to use some form of clientside javascript.

ViSoft, I put the code below in my application and nothing happens. The casing look correct to me with my limited javascript exposure.. What could be wrong?



I put this into the head of the masterpage:

<script type="text/javascript">

function CalculateTotal()
{
var Sum;
Sum=0;

if (document.getElementById('txtSubtotal').value !="")
Sum = Sum  + Number(document.getElementById('txtSubtotal').value);

if (document.getElementById('txtTax').value !="")
Sum = Sum  + Number(document.getElementById('txtTax').value);

if (document.getElementById('txtMisc').value !="")
Sum = Sum  + Number(document.getElementById('txtMisc').value);

if (document.getElementById('txtShipping').value !="")
Sum = Sum  + Number(document.getElementById('txtShipping').value);

document.getElementById('lblTotal').innerHTML = Sum;
return false;
}

</script>


I put this in each textbox control:

 onchange="javascript:return CalculateTotal();"

Additional info which may change things. The controls are within a usercontrol that I place on the page that loads into the masterpage with the javascript. Also, when the usercontrol is first loaded the text boxes are set to false. It is not untill products and shipping are added that the textboxes are set to visible = true...

For anyone coming along later. To get the javascript to work you have to have the correct getElementById for each control. To get this just view source of the page when running as the name of the control that the javascript can see is based on where the control resides.

For example:

ctl00_ContentPlaceHolder1_ctlCreateOrder_txtSubTotal

Note that the control may change.  There is a .clientID on the ASPX side which you can pass to the javascript.

Thank you ged325! I have read that but did not know how to actually modify the JavaScript since the textbox and label controls are in a usercontrol on a child page of a mater page... Do you know what I should modify?