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Hi i yogesh sharma. my problem is that i want to display the length of text as i type in a textbox, i have set the autopostback property of textbox to true, i write the following code on the textchanged event.
protected void txtsubject_Textchanged(Object sender,EventArgs e)

NOW iam getting the length of txtsubject.text in textbox1,but after the completion of the entire text in txtsubject(after pressing tab).
But I want the length of txtsubject.Text in textbox1 as i type correspondingly in txtsubject.
Please tel me what's the problem with my code. I have also set the autopostback to true. which i really does'nt want.
Please help me.. friends....Its urgent..I Have master page attached with my page having textbox. so please suggest me solution... where to use javascript function i:e in masterpage or in child page and in which tag...
Updated 18-Aug-11 7:18am

You have to use Javascript for that.

Just Google this.

A good example is here.
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You can use javascript

    <script type="text/javascript">
        function Init () {
            var counter = document.getElementById ("counter");
            for (var i = 1; i < 1000; i++) {
                var option = new Option (i, i);
                counter.options.add (option);
            counter.focus ();

        function OnKeyPressCounter (event, counter) {
            var chCode = ('charCode' in event) ? event.charCode : event.keyCode;

            if (chCode == 43 /* + */) {
                if (counter.selectedIndex < counter.options.length - 1) {
            if (chCode == 45 /* - */) {
                if (counter.selectedIndex > 0) {
<body onload="Init ()">
    Use the + and - keys to increase/decrease the counter.
    <select id="counter" onkeypress="OnKeyPressCounter (event, this)" style="width:80px"></select>
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Hi You Can use Javascript to achieve this.
Add following JavaScript function to yoyur page

function ShowTextLength()
            var objLbl = document.getElementById("lblTextLength");
            var objTxt = document.getElementById("txtBox");
            if(objLbl && objLbl)
                objLbl.innerText = objTxt.value.length;

Call this function on body Load and key up event of text box,

<body  önload="ShowTextLength();"></body>

Add Text Box and Labels on the page

<asp:textbox id="txtBox" runat="server" onkeyup="ShowTextLength();">
        <br />
        <asp:label id="lblTextLength" runat="server">

Here I have used Label to display length of the text present in text box, you can take any control and modify last line of the javascript function as per control.
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