The comboBox has a couple of server side events to deal with field changing.
How can we catch the comboBox changing on the client side?
Without access to these function on the client side, we need to use the client side events of the textBox that is contained within the comboBox. As with any textBox this one also has the onChange event, but the event does not run when the text was changed and the focus moved to another field. There are a few options:
protected void Page_Load(object sender, EventArgs e)
TextBox textBox = cmbExample.FindControl("TextBox") as TextBox;
if (textBox != null)