Difference between revisions of "Case"
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| − | # | + | Case opens a case statement. The case statement compares the value of ordinal expression to each selector, which can be a [[Const|constant]], a subrange, or a list of them separated by [[Comma|commas]]. Selector field separated to action field by [[Colon]]. |
| + | |||
| + | The case statement include [[Reserved word|reserved words]] [[Of]] and [[End]] . Sometimes [[Else]]. too. | ||
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| + | <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 == | ||
| + | |||
| + | * [[doc:/ref/refsu40.html#x110-11700010.2.2| The Case statement]] | ||
| + | * [[doc:/ref/refsu15.html#x38-450003.3.2| Record types]] | ||
Revision as of 10:30, 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>
