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I have two textboxes.

I will calculate the values of two text box inputs then when I click on 3rd text box then the calculated value will be shown on the 3rd text box.

Can anyone please tell me how to do that?

You can only give me solution about that click event.
Updated 19-Oct-10 21:43pm
Dalek Dave 20-Oct-10 3:43am    
Edited for Readability.

You need to use Js onFocus Event.

Suppose there are three textbox named,


Then write onFocus Event on TextBox3 Like.

<asp:textbox id="TextBox3" runat="Server" onfocus="javascript:focused(this)" xmlns:asp="#unknown" />

function focused(txt3)
var result = document.getElementById("TextBox1").value * document.getElementById("TextBox2").value;
            txt3.value = result;


[Additional answer]
You could use THIS[^]
[/additional answer] to count date difference.

and your'e done.

Please vote and Accept Answer if it Helped.
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sazib 20-Oct-10 5:16am    
Thanks for your reply.You solution works well for any values.But I have to work with dates. I've two text box startdate and enddate. I will input two date into two text box one is txtBoxStartDate and another one txtBoxEndDate. I want to show the duration of these two dates after I click on duration text box. Can you please tell me the whole procedure using javascript or jquery? I know the calculation in C# but as I'm a beginner of javascript,so I need your help.
Hiren solanki 20-Oct-10 5:19am    
duration in minutes,seconds,hours... ???
sazib 20-Oct-10 5:48am    
I need only days.nothing else.
Hiren solanki 20-Oct-10 5:53am    
see my additional answer.
use the enter event of the textbox ..

use the below code

<pre lang="cs">private void textBox3_Enter(object sender, EventArgs e)
           textBox3.Text = Convert.ToString (Convert.ToInt32(textBox1.Text) + Convert.ToInt32(textBox2.Text));

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Hiren solanki 20-Oct-10 3:05am    
Question is from, and it doesn't support _enter event.
Rajesh Anuhya 20-Oct-10 3:06am    
ohhh.., am sorry i just confused,,
sazib 20-Oct-10 4:09am    
Thanks for your ans. It's not working the way I need to.I've two text box startdate and enddate. I want to show the duration of these two dates after I click on duration text box. I know the calculation but I don't know how to automatically put the duration value after just a single click on duration textbox.
Rajesh Anuhya 20-Oct-10 6:04am    
hi "madhukk" .., why u edited my answers as "OnTextChanged" instead of "Enter" event(which i write).., is there any specific reason?????????
do it on blur like it drag a button and on button click write ur code:

textBox3.Text = Convert.ToString (Convert.ToInt32(textBox1.Text) + Convert.ToInt32(textBox2.Text));

onload event of page write this

protected void Page_Load(object sender, EventArgs e)
Button1.Visible = false;
string handler = ClientScript.GetPostBackEventReference(this.Button1, "");
TextBox2.Attributes.Add("onblur", handler);
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Mohd Wasif 20-Oct-10 6:05am    
also add EnableEventValidation="false" in design of page[^] try this link...............otherwise u can use javascript to implement this............
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