Panel Size keep getting smaller

Question

I got many panels and one form. I have employed panels so I don't have to use multiple forms. But there is a problem with it. After I assign the panel size to the form size and show the form, the next time I assign it again, and to my surprise the panel gets smaller than the original. Why is this happening? Here is how I'm doing it.

this.Size = panelABC.Size;
panelABC.Dock = DockStyle.Fill;
panelABC.Visible = true;

Answer 1

Because the panel size has changed in relation to the control it is docked within by the time you come to call this code again. Using docking or anchoring will manage the panel size during resizing of parent containers.

For answer clarity - the actual answer is described in the comments of another posted answer.

Answer 2

I would assume that there is some padding or other that means that after the first assignment some resizing needs to happen to fit things meaning that panelABC gets smaller (so it will fit correctly). Thus recursive calls make it keep getting smaller.

To confirm if this is the case stick in a breakpoint and check what your Sizes are as you go through...

Answer 3

What's this? If it's the form (or parent control) your panel lives in then that's your problem: docking your panel will make it slightly smaller than the parent. Subsequent calls to your code then make the parent match the panel's (smaller) size, and then you repeat the process...