Community resource center

Restricting the length of text on a Multi line textbox is not supported by the standard ASP.NET Web control. This can be done by adding the following Javascript function in your ASPX page.

1. Add a javascript:

At the top of your ASPX page you will see the following tag </ head > . A dd the following code under this tag:

<script language="javascript" type="text/javascript">function Count(text,long)

{

    var maxlength = new Number(long); // Change number to your max length.

    if (text.value.length > maxlength){

        text.value = text.value.substring(0,maxlength);

        alert(" Only " + long + " chars");

    }

}

</script>

2. Change your text controls on your ASPX page

On every multi-line text box where you would like to control the length, add the following code to the asp text box control.

onKeyUp="Count(this,50)" onChange="Count(this,50)"

Your original text control before adding this code:

<asp:TextBox ID="TESTDATA" runat="server" TextMode="MultiLine"></asp:TextBox>

After adding the code:

<asp:TextBox ID="TextBox1" runat="server" onKeyUp="Count(this,50)" onChange="Count(this,50)" TextMode="MultiLine"></asp:TextBox>