Restrict the form size in Delphi

Anyone who has used Delphi will notice the top window of Delphi itself,

When it is very large, it only occupies a small part of the screen. How does it implement it? See the following description:

1) Add the following line to the form private declaration:

Proceduremessage: twmgetminmaxinfo); message wm_getminmaxinfo;

Wmgetminmaxinfo (VAR

2) Add the following lines to the Declaration:

Procedure tform1.wmgetminmaxinfo (VAR message: twmgetminmaxinfo );
Begin
With message. minmaxinfo ^ do
Begin
Ptmaxsize. X: = 200; {maximum width}
Ptmaxsize. Y: = 200; {maximum height}
Ptmaxposition. X: = 99; {the abscissa in the upper left corner of the maximized value}
Ptmaxposition. Y: = 99; {upper-left column coordinate when maximization}
End;
Message. Result: = 0; {tell windows that you have changed minmaxinfo}
Inherited;
End;

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