How to disable asp:TextBox on client-side click on HTML checkbox or server-side asp:CheckBox using JavaScript?
<script type="text/javascript" language="javascript">
function enableTextbox() {
// ?
}
</script>
<table>
<tr>
<td>
<input id="checkTake" onclick="enableTextbox" title="Take?" />
</td>
</tr>
<tr>
<td>
<asp:TextBox runat="server" ID="txtCommission" />
</td>
</tr>
</table>
The tricky part here is that ASP.NET assigns autogenerated id attributes for all runat="server" elements, inlcluding your TextBox. A simple solution is to "inject" the generated id into the script:
function enableTextbox() {
var txtCommision = document.getElementById("<%= txtCommision.ClientID %>");
txtCommision.disabled = !this.checked;
}
If you prefer to do it without this type of "spaghetti code" - maybe you want your JavaScript in a seperate file - you can avoid using the id for selecting the <input> field. Instead you can decorate it with a class. In that case, you might want to use some kind of selector library to find the control in JavaScript, jQuery being a popular option.
<script type="text/javascript" language="javascript">
function enableTextbox(checkbox) {
document.getElementById('<%= txtCommission.ClientID %>').disabled = !document.getElementById(checkbox).checked;
}
</script>
<table>
<tr>
<asp:CheckBox runat="server" ID="checkTake" onclick="enableTextbox(this.id)" Checked="true" Text="Take?" />
</tr>
<tr>
<td>
<asp:TextBox runat="server" ID="txtCommission" MaxLength="8" CssClass="right" />
</td>
</tr>
</table>
function enableTextbox() {
document.getElementById("<%= txtCommision.ClientID %>").disabled = !document.getElementById("checkTake").checked;
};
You need to actually invoke enableTextbox as well:
<input id="checkTake" onclick="enableTextbox()" title="Take?" />
jQuery:
$(document).ready(function () {
$('#checkTake').bind('click', function () {
$('#<%= txtCommission.ClientId %>').attr('disabled', !$(this).attr('checked'));
});
});
