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Checked State

This help article showcases how to check/uncheck the RadCheckBox control on the server-side/client-side.

Get/Set Checked State Server-Side

You can get/set the checked state of the RadCheckBox control on the server-side through the Checked property.

The Checked property takes a nullable boolean. When a null value is set, the Checked value will default to false. This is useful for data-binding scenarios when the Checked property is bound to a data source field of nullable boolean type.

Example 1: Check RadCheckBox in the markup.

<telerik:RadCheckBox ID="RadCheckBox1" runat="server" Text="I agree" Checked="true"></telerik:RadCheckBox>

Example 2: Get/Set the Checked property from the server-side.

protected void Page_Init(object sender, EventArgs e)
{
    bool isChecked = RadCheckBox1.Checked;
    RadCheckBox1.Checked = !isChecked;
}
Protected Sub Page_Init(sender As Object, e As EventArgs)
    Dim isChecked As Boolean = RadCheckBox1.Checked
    RadCheckBox1.Checked = Not isChecked
End Sub

Get/Set Checked State Client-Side

To get/set the checked state of the RadCheckBox control on the client-side you can use the get_checked() and set_checked() properties of the control.

Example 3: Toggle the initial checked state of RadCheckBox.

function pageLoad() {
    var checkBox = $find("<%=RadCheckBox1.ClientID%>");
    var isChecked = checkBox.get_checked();
    checkBox.set_checked(!isChecked);
}
<telerik:RadCheckBox ID="RadCheckBox1" runat="server" Text="I agree" Checked="true"></telerik:RadCheckBox>

See Also

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