Delphi Basics : Bounds command

DelphiBasics

Bounds
Function

Create a TRect value from top left and size values

Classes unit

function Bounds(const Top, Left, Width, Height Integer):TRect;

Description

The Bounds function creates a TRect rectangle value from Top, Left coordinates, and Width, Height size values.

It provides a useful alternative to the Rect function, where you must know the bottom and right coordinates rather than the rectangle size.

Related commands

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
TRect		Holds rectangle coordinate values

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Example code : Create rectangles using Rect and Bounds

var
  rectangle1, rectangle2 : TRect;

begin
  // Set up the first rectangle using the Rect function
  // Note that we override the Types version of Rect.
  rectangle1 := Classes.Rect(Point(10, 60), Point(50, 80));

  // Set up an identical 2nd rectangle using the Bounds function
  rectangle2 := Bounds(10, 60, 40, 20);

  // 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 = 10,60,50,80
Rectangle 2 coords = 10,60,50,80