Repeat statements whilst a continuation condition is met
 keyword While(While Expression do Statement;
The While keyword starts a control loop that is executed as long as the Expression is satisfied (returns True).
The loop is not executed at all if the expression is false at the start.
You need Begin or End markers if multiple statements are required in the loop.
It is used when it is important that the statements are at only executed when necessary.
Related commands
BeginKeyword that starts a statement block
BooleanAllows just True and False values
DoDefines the start of some controlled action
EndKeyword that terminates statement blocks
ForStarts a loop that executes a finite number of times
RepeatRepeat statements until a ternmination condition is met
UntilEnds a Repeat control loop
 Download this web site as a Windows program.

Example code : Display integer squares until we reach 100
  num, sqrNum : Integer;

  num := 1;
  sqrNum := num * num;

  // Display squares of integers until we reach 100 in value
  While sqrNum <= 100 do
    // Show the square of num
    ShowMessage(IntToStr(num)+' squared = '+IntToStr(sqrNum));

    // Increment the number

    // Square the number
    sqrNum := num * num;
Show full unit code
  1 squared = 1
  2 squared = 4
  3 squared = 9
  4 squared = 16
  5 squared = 25
  6 squared = 36
  7 squared = 49
  8 squared = 64
  9 squared = 81
  10 squared = 100
Delphi Programming © Neil Moffatt . All rights reserved.  |  Home Page