There is a PUSBUTTON control or DEFPUSHBUTTON control.
 
Syntax:
Window.AddControl(id, 0, X, Y, W, H, "Text"); // PUSHBUTTON
Window.AddControl(id, 1, X, Y, W, H, "Text"); // DEFPUSHBUTTON
Sample:
Window.AddControl(100, 0, 0, 0, 80,12,"Usual button");
Window.AddControl(200, 1, 0,12, 80,12,"By default");
Description:
A push button is a rectangle (X, Y, W, H) containing application-defined text (label) that indicates what the button does when the user selects it. A standard push button is typically used to start an operation.

X, Y, W, H :- The horizontal base unit is equal to the average width, in pixels, of the characters in the system font; the vertical base unit is equal to the height, in pixels, of the font. Furthermore, each horizontal base unit is equal to 4 horizontal dialog units; each vertical base unit is equal to 8 vertical dialog units.

 
  GUI for script  
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