To Overcome Length Problem of Textarea in Asp.net

<asp:TextBox runat="server" style="overflow:hidden;" ID="txtAreaCommets" Font-Size="11px" TextMode="MultiLine" Text='<%# Bind("ProcessedRemarks") %>' Rows="2" Width="99.5%" oncopy="return false" oncut="return false" onpaste="return false" onkeypress="if (this.value.length > 250) { return false; }"></asp:TextBox>