Javascript – Checkbox to Control Button Enabled Property – ASP.NET

asp.netc++javascript

I would like to know how I can control the 'Enabled' property of a button based on the 'checked' value of a checkbox:

<asp:CheckBox ID="chkEnableButton" runat="server" />
<asp:Button ID="btnLoadForm" runat="server" />

I can do this very easily on the server side – but I require this to be done on client side only, meaning JavaScript. Would the OnCheckedChanged attribute allow me to call some JavaScript to do this….or is it strictly for calling a handler in the code-behind?

Just to clarify, when the checkbox is checked, the button is enabled… when the checkbox is unchecked the button is disabled.

Best Solution

Javascript:

<script type="text/javascript">
function checkButt(obj) {
    document.getElementById('<%=btnLoadForm.ClientID%>').disabled = !obj.checked;
}
</script>

Web Controls:

<asp:CheckBox ID="chkEnableButton" runat="server" OnClientClick="checkButt(this);" />
<asp:Button ID="btnLoadForm" runat="server" />

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Best Solution

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