Difference between revisions of "Case"

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== Read more ==
 
== Read more ==
  
* [[doc:/ref/refsu40.html#x110-11700010.2.2| The Case statement]]
+
* [http://www.freepascal.org/docs-html/ref/refsu40.html#x110-11700010.2.2 The Case statement]]
* [[doc:/ref/refsu15.html#x38-450003.3.2| Record types]]
+
* [http://www.freepascal.org/docs-html/ref/refsu15.html#x38-450003.3.2  Record types]

Revision as of 09:58, 17 August 2008

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

The case statement include reserved words Of and End . Sometimes Else. too.


<delphi>

case place of
  1: ShowMessage('Cold medal');
  2: ShowMessage('Silver medal');
  3: ShowMessage('Bronze medal'); 
  else ShowMessage('Next time: Good luck'); 
end;

</delphi>

Variant Record

Case-word is used Variant Record, too. Variant Record also called a tagged union.

<delphi>

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

</delphi>

Read more