Runtime Type Information (RTTI)

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Runtime Type Information RTTI can be utilized to obtain meta information in a Pascal application.

Converting a enumerated type to a string

One can use RTTI to obtain a string from a enumerated type.

uses TypInfo; 

type
  TProgrammerType = (tpDelphi, tpVisualC, tpVB, tpJava) ;

var 
  s: string;
begin
  s := GetEnumName(TypeInfo(TProgrammerType), integer(tpDelphi));
  // Here s = 'tpDelphi'
  WriteLn(s)
end.

But you can also do it without RTTI:

program noRTTI;
type
  TProgrammerType = (tpDelphi, tpVisualC, tpVB, tpJava) ; 
var 
  s: string;
begin
  writestr(s, tpDelphi);
  WriteLn(s);
end.

See Also