Runtime Type Information (RTTI): what changed
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Title: Runtime Type Information (RTTI)
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| 1 | + | **Runtime Type Information RTTI** can be utilized to obtain meta information in a Pascal application. | |
| 2 | + | ||
| 3 | + | ## Converting a enumerated type to a string | |
| 4 | + | ||
| 5 | + | One can use RTTI to obtain a string from a enumerated type. | |
| 6 | + | ||
| 7 | + | ``` pascal | |
| 8 | + | uses TypInfo; | |
| 9 | + | ||
| 10 | + | type | |
| 11 | + | TProgrammerType = (tpDelphi, tpVisualC, tpVB, tpJava) ; | |
| 12 | + | ||
| 13 | + | var | |
| 14 | + | s: string; | |
| 15 | + | begin | |
| 16 | + | s := GetEnumName(TypeInfo(TProgrammerType), integer(tpDelphi)); | |
| 17 | + | // Here s = 'tpDelphi' | |
| 18 | + | WriteLn(s) | |
| 19 | + | end. | |
| 20 | + | ``` | |
| 21 | + | ||
| 22 | + | But you can also do it without RTTI: | |
| 23 | + | ||
| 24 | + | ``` pascal | |
| 25 | + | program noRTTI; | |
| 26 | + | type | |
| 27 | + | TProgrammerType = (tpDelphi, tpVisualC, tpVB, tpJava) ; | |
| 28 | + | var | |
| 29 | + | s: string; | |
| 30 | + | begin | |
| 31 | + | writestr(s, tpDelphi); | |
| 32 | + | WriteLn(s); | |
| 33 | + | end. | |
| 34 | + | ``` | |
| 35 | + | ||
| 36 | + | ## See Also | |
| 37 | + | ||
| 38 | + | - [[RTTI tab]] | |
| 39 | + | - [[RTTI controls]] | |
| 40 | + | - [Run-Time Type Information In Delphi - Can It Do Anything For You?](http://www.blong.com/Conferences/BorConUK98/DelphiRTTI/CB140.htm) | |
| 41 | + | ||
| 42 | + | --- | |
| 43 | + | *From the Free Pascal wiki, page "Runtime Type Information (RTTI)", as it stood on 2020-02-25 after a change by Trev, out of the wiki's dump of 2024-05-26. Copyright stays with the author who wrote it, according to the old wiki's [[Licensing]] page. If you have concerns about this material, [message the admin](/wiki-contact).* |