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I want to execute server side method to calculate sum of two textbox's values in third textbox in but I don't know how to do it.

I had tried lot of javascript but it is giving me error.

can any one tell me how to do it.

thnx in advance

I have three text box

I want to do
txt_amount.text=txt_qty.text * txt_rate.text
Updated 5-May-13 9:14am
Please post your code...
Maciej Los 5-May-13 13:32pm    
Show us code of your site. Use "Improve questtion" widget.
[no name] 5-May-13 14:22pm    
In addition to posting the code that you have written that demonstrates your problem, it would be nice to know what the error is.

<asp:textbox id="txt_qty" runat="server" xmlns:asp="#unknown"></asp:textbox>

<asp:textbox id="txt_rate" runat="server" autopostback="True" ontextchanged="txt_rate_TextChanged" xmlns:asp="#unknown"></asp:textbox>

<asp:textbox id="txt_amount" runat="server" xmlns:asp="#unknown"></asp:textbox>

protected void txt_rate_TextChanged(object sender, EventArgs e)

        /*implement your calculations here*/
        txt_amount.text=txt_qty.text * txt_rate.text;
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jagdish123061 6-May-13 2:52am    
Thnx rohan leuva it worked but i want to do it without postback can u give me code in javascript
If you mean .NET event, you should understand: you cannot raise event (correct term is: invoke event) from nowhere except the class where the event instance is declared. You cannot do this even in the derived class. Why? This is one of the limitations of events, compared to the "regular" delegate, an important fool-proof feature.

As you are talking about the event already declared in the library, there is no a way to invoke it in any other way; except the case when you actually change text of the control. So what to do? As this is the fool-proof feature, apparently, a way to go is not to be one of those fool. :-) You never really need to invoke this event, but probably you simply need to have the same effect as the one caused by this event. Then do exactly this.

Develop some method you want to be called when the text is modified. Call this event in two places: in the handler of the event (and then don't do anything else in you handler) and elsewhere. Problem solved.

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