type
TRect = packed record
case Integer of
0: (Left, Top, Right, Bottom: Integer);
1: (TopLeft, BottomRight: TPoint);
end;
Description
The TRect type is a record holding rectangle values as either 4 coordinates or 2 points.
This is a classic example of the use of the Case part of a record.
When creating from two points TopLeft and BottomRight, you can pass two TPoint values, or use the Point function to generate them.
Related commands
Bounds Create a TRect value from top left and size values
Point Generates a TPoint value from X and Y values
PointsEqual Compares two TPoint values for equality
PtInRect Tests to see if a point lies within a rectangle
Rect Create a TRect value from 2 points or 4 coordinates
TPoint Holds X and Y integer values
Example code : Create one rectangle manually, another using Rect
var
rectangle1, rectangle2 : TRect;
begin
// Set up the first rectangle manually
rectangle1.Left := 0;
rectangle1.Top := 0;
rectangle1.Right := 40;
rectangle1.Bottom := 60;
// Set up the second rectangle using the Rect function
rectangle2 := Rect(Point(20, 40), Point(60, 80));
// Display the top left and bottom right coords of each rectangle
ShowMessageFmt('Rectangle 1 coords = %d,%d,%d,%d',
[rectangle1.Left,
rectangle1.Top,
rectangle1.Right,
rectangle1.Bottom]);
ShowMessageFmt('Rectangle 2 coords = %d,%d,%d,%d',
[rectangle2.Left,
rectangle2.Top,
rectangle2.Right,
rectangle2.Bottom]);
end;
Show full unit code
Rectangle 1 coords = 0,0,40,60
Rectangle 2 coords = 20,40,60,80