Question

I have button named “Paint” which should allow drawing rectangle on my picturebox after a click, i.e. it acts like a switch to allow drawing(on/off).

I’ve drawn rectangle using mouse positions as explained here: How Can I Capture Mouse Coordinate on PictureBox? . But rectangle is drawn whenever I move over PictureBox.

How can I implement the functionality where drawing must be implemented only when “Paint” is ‘on’
I’ve tried starting implementation from events of Picturebox: Paint, MouseDown, MoseMove, Mouse Up…

Answer 1

1. set a flag(bool) in your application telling you the mode you are in whether drawing or not(can be activated from the button you are telling about).

2. in mouse down take the start point(e.x, e.y) from the mouse event handler.
   now you have the top left point of the rectangle.

   3.while mouse move take e.x and e.y and which is the bottom right point and draw your rectangle. put the drawing code in mouse move so that the it draws like the “Paint” Program(do this if the draw flag is true).

3. in mouse up reset the drawing flag

   5.in the paint event of the picturebox draw the all the shapes you have so that if you minimized your application windows and then maximized it you will find your shapes drawn this can be achieved by making the rectangle is a class and make some instances of it(for loop over your shapes and draw it).