TextChanged Event
The radtextbox control provides 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, the TextChanged event does not occur.
The postback request can be controlled for RadTextBox by using the OnValueChanged client event of the control.
The TextChanged event handler receives two arguments:
The RadInput control whose value was just changed. This argument is of type object, but can be cast to the appropriate type.
An EventArgs object.
Use the TextChanged event handler to respond to changes in the control's text:
protected void RadInput_TextChanged(object sender, EventArgs e)
{
if (sender is RadTextBox)
{
RadTextBox tb = (RadTextBox)sender;
Image1.ImageUrl = @"~/Images/" + tb.Text + ".gif";
}
}
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"
End If
End Sub