Maxlength for multiline textbox in ASP.NET page using AJAX

Easy solution for restricting text to MAXLENGTH in a multiline textbox, using Ajax MaskedEdit extender.

To get the effect of Maxlength=50, just attach the MaskedEdit extender to the multiline textbox and set the Mask value to ?{50}.

Following example shows a 'Maxlength' of 300.

<asp:TextBox ID="TextBox1" runat="server" Text='<%# Bind("Remarks") %>' Width="700px" TextMode="MultiLine"></asp:TextBox>

<cc1:MaskedEditExtender ID="MaskedEditExtender1" runat="server" Mask="?{300}" PromptCharacter="" TargetControlID="TextBox1">
</cc1:MaskedEditExtender>