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Count number of characters in textbox

Markup Page

<strong>Required Info:</strong> 
<asp:Label ID="TotCharReqInfo" runat="server" ></asp:Label>  

<strong>Body Length:</strong> 
<span id="BodyLength">0

<strong>Total Length:</strong> <span id="TotLength"> 
<asp:Label ID="TotLengthLbl" runat="server" ></asp:Label>

<strong>Left:</strong> <span id="CharLeft">
<asp:Label ID="ChLeft" runat="server" ></asp:Label>


<asp:TextBox id="txtInputOnln" runat="server" 
    TextMode="MultiLine" Width="300px" Height="90px" 
    MaxLength="350" onKeyUp="Count(this,350)" 
    onChange="Count(this,350)"/>


<script type="text/javascript"> var ChLeftVar = "<%=CharLeftInt %>"; var ChLeftOut var ChLefVar2 function count(clientId) { var txtInputOnln = document.getElementById(clientId); var CharLeft = document.getElementById('CharLeft'); var BodyLength = document.getElementById('BodyLength'); var TotLength = document.getElementById('TotLength'); BodyLength.innerHTML = txtInputOnln.value.length; ChLeftOut = 350 - ChLeftVar ChLeftVar2 = (350 - ChLeftOut) + txtInputOnln.value.length; TotLength.innerHTML = ChLeftVar2; CharLeft.innerHTML = ChLeftOut - txtInputOnln.value.length; } //limit user input (350 this case) function Count(text, long) { var maxlength = new Number(ChLeftOut); // Change number to your max length. if (text.value.length > maxlength) { text.value = text.value.substring(0, maxlength); // alert(" Only " + long + " chars");// alert(" Only 350 characters "); } } </script> Code Behind Protected CharLeftStr As String Protected CharLeftInt As Integer Dim count As Integer = 0 Dim ReqInfoTot As String = TxtBx1.Text + TxtBx2.Text + TxtBx3 For Each c As Char In ReqInfoTot If Char.IsLetter(c) Or Char.IsNumber(c) Then count += 1 End If Next TotCharReqInfo.Text = count.ToString() - 2 TotLengthLbl.Text = count.ToString() - 2 '(2) is number of "+" inside the ReqInfoTot string txtInputOnln.Attributes("onkeydown") = = String.Format("count('{0}')", txtInputOnln.ClientID) ChLeft.Text = 350 - TotCharReqInfo.Text.ToString() CharLeftStr = TotCharReqInfo.Text.ToString() CharLeftInt = Convert.ToInt32(CharLeftStr)