Case

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Case opens a case statement. The case statement compares the value of an ordinal expression to each selector, which can be a constant, a subrange, or a list of them separated by commas. The selector field is separated from action field by Colon.

The case statement includes the reserved words Of and End. Else can be used if needed, too.


 case place of
   1: ShowMessage('Gold medal');
   2: ShowMessage('Silver medal');
   3: ShowMessage('Bronze medal'); 
   else ShowMessage('Better luck next time'); 
 end;

WhatIsChar

 function WhatIsChar( c:char ):string;
 var
   s : string;
 begin
   s := '';
   case c of
     '0' .. '9' : s := 'digit (0-9)';
     'a' .. 'z' : s := 'lowercase letter (a-z)';
     'A' .. 'Z' : s := 'uppercase letter (A-Z)';
     '+' , '-'  : s := 'sign (+ or -)';
   end;
   result := s;
 end;

Variant Record

Case is used in Variant Record, too. A Variant Record is also called a tagged union.

  type
 
   ScaleKelvin = 223 .. 323;
   ScaleCelsius = -50 .. 50;
 
   TemperatureScale = ( celsius, kelvin ) ;
   Temperature = record
    case scale :   TemperatureScale of
     celcius : (celsius_value : ScaleCelsius);
     kelvin : (kelvin_value : ScaleKelvin);
   end;

See also

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