Using Controls in Dialog Boxes

You use controls in dialog boxes much as you use them in regular windows. When a control is in a dialog box, however, you can use several special functions to access the control and send messages to it. For example, the SendDlgItemMessage function sends a message to a control in the dialog box, and the SetDlgItemText function sets the text of a control. You do not need to supply the control handle in these functions. Instead, you supply the dialog handle and the control ID. If you want the control handle, you can use the GetDlgItem function.