All RadInput controls provide the TextChanged server event, which is raised when the AutoPostBack property is set to true, the user types valid entry, and the input loses focus.

The TextChanged event only occurs if the value of the input control actually changes. If the user changes the string in the input control but does not actually change the value (for example, entering a date into RadDateInput using a different format or entering an out-of-range number that is automatically corrected to the old value by RadNumericTextBox), the TextChanged event does not occur.

Note
Note that when using RadNumericTextBox, if a value is passed from the server with more digits after the decimal point than you have specified through the NumberFormat.DecimalDigits property, on postback the TextChanged event will fire, as the rounding done on the client by the RadNumericTextBox in fact changes the initial value. This would happen even when there was no user action on the textbox.

Note
The postback request can be cancelled for RadDateInput, RadNumericTextBox and RadTextBox by using the OnValueChanged client event of the control.

The TextChanged event handler receives two arguments:

1. The RadInput control whose value was just changed. This argument is of type object, but can be cast to the appropriate type.

2. An EventArgs object.

Use the TextChanged event handler to respond to changes in the control's text:

• C#
• VB.NET

Copy[C#] TextChanged

protected void RadInput_TextChanged(object sender, EventArgs e)
{
    if (sender is RadTextBox)
    {
        RadTextBox tb = (RadTextBox)sender;
        Image1.ImageUrl = @"~/Images/" + tb.Text + ".gif";
    }
    else if (sender is RadNumericTextBox)
    {
        RadNumericTextBox ntb = (RadNumericTextBox)sender;
        RadComboBox1.SelectedIndex = ntb.Value;
    }
    else if (sender is RadMaskedTextBox)
    {
        RadMaskedTextBox mtb = (RadMaskedTextBox)sender;
        HttpCookie = Response.Cookies.Get(mtb.TextWithLiterals);
        Button1.Enabled = (HttpCookie != null);
    }
    else if (sender is RadDateInput)
    {
        RadDateInput di = (RadDateInput)sender;
        RadCalendar1.SelectedDate = di.SelectedDate;
    }
}

Copy[VB] TextChanged

Protected Sub RadInput_TextChanged(ByVal sender As Object, ByVal e As EventArgs) Handles RadTextBox1.TextChanged, RadNumericTextBox1.TextChanged, RadMaskedTextBox1.TextChanged, RadDateInput.TextChanged
    If TypeOf sender Is RadTextBox Then
        Dim tb As RadTextBox = DirectCast(sender, RadTextBox)
        Image1.ImageUrl = "~/Images/" + tb.Text + ".gif"
    ElseIf TypeOf sender Is RadNumericTextBox Then
        Dim ntb As RadNumericTextBox = DirectCast(sender, RadNumericTextBox)
        RadComboBox1.SelectedIndex = ntb.Value
    ElseIf TypeOf sender Is RadMaskedTextBox Then
        Dim mtb As RadMaskedTextBox = DirectCast(sender, RadMaskedTextBox)
        HttpCookie = Response.Cookies.[Get](mtb.TextWithLiterals)
        Button1.Enabled = (HttpCookie <> Nothing)
    ElseIf TypeOf sender Is RadDateInput Then
        Dim di As RadDateInput = DirectCast(sender, RadDateInput)
        RadCalendar1.SelectedDate = di.SelectedDate
    End If
End Sub