Textbox value automatic change

[soona]

hi Experts,In javascript :-> how to change text box value automatically ? when will give text box value from another input box?I gave code below.pls check . where i made mistake.----------------------------------------The javascript code as follows:<script language="javascript" type="text/javascript">function Fn_Add(){var first ="0"var second="0"var third="0"if(document.getElementById ("TextBox1").value!=""){first =document.getElementById ("TextBox1").value}else{document.getElementById("TextBox1").value="0"}if(document.getElementById ("TextBox2").value!=""){second=document.getElementById ("TextBox2").value}else{document.getElementById("TextBox2").value="0"}if(document.getElementById ("TextBox3").value!=""){third=document.getElementById ("TextBox3").value}else{document.getElementById("TextBox3").value="0"}document.getElementById ("TextBox4").value=parseInt(first)+parseInt(second) + parseInt(third)}</script>------------------------------------------now i given Three(3) Textbox value add And Result display in TextBox4...suppouse you given TextBox1 & TextBox3 value(ex:100,200) but didn't given TextBox2 values in run time...TextBox2 value built in 0 automaticaly...At that time of running in webpage you make it to change Each & Every single digit value in any Textbox automaticaly change the Result value...With kind regardsNancy

[MinusMyThoughts]

You need to have a function that runs onchange. That way, when a value changes, the function is triggered and will recalculate the values.

<script type="text/javascript">function recalc() {  // code to check textbox 1	. . .  // code to check textbox 2	. . .  // code to check textbox 3	. . .  // add them up, change the text   document.getElementById("TextBox4").value = tb1+tb2+tb3;}</script><input id="TextBox4" type="text" value="" onChange="java script:recalc();" />

Something like that will at least get you headed in the right direction.-Jason