Difference between revisions of "TFPGMap"
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TFPGMap is part of the <code>FGL</code> (Free Generics Library). | TFPGMap is part of the <code>FGL</code> (Free Generics Library). | ||
+ | ==Example== | ||
Here is an example provided by forum user '''Remy Lebeau''': | Here is an example provided by forum user '''Remy Lebeau''': | ||
Line 23: | Line 24: | ||
</syntaxhighlight> | </syntaxhighlight> | ||
+ | ==IndexOfData== | ||
+ | By default <code>TFPGMap<></code> does not provide a comparison for the Data type. So method IndexOfData will not find anything. You need to provide it by assigning the OnDataCompare event: | ||
+ | |||
+ | <syntaxhighlight lang="pascal"> | ||
+ | uses | ||
+ | StrUtils, fgl; | ||
+ | |||
+ | {$R *.lfm} | ||
+ | |||
+ | type | ||
+ | TMyTest = specialize TFPGMap<PtrInt, String>; | ||
+ | ... | ||
+ | public | ||
+ | property MyTest: TMyTest read FMyTest write SetMyTest; | ||
+ | end; | ||
+ | ... | ||
+ | |||
+ | function CompareStringFunc(const aData1, aData2: String): Integer; | ||
+ | begin | ||
+ | Result := AnsiCompareStr(aData1, aData2); | ||
+ | end; | ||
+ | |||
+ | procedure TForm1.FormCreate(Sender: TObject); | ||
+ | var | ||
+ | i: PtrInt = 0; | ||
+ | begin | ||
+ | FMyTest:= TMyTest.Create; | ||
+ | FMyTest.OnDataCompare := @CompareStringFunc; | ||
+ | </syntaxhighlight> | ||
==See also== | ==See also== | ||
* https://www.freepascal.org/docs-html/current/rtl/fgl/tfpgmap.html | * https://www.freepascal.org/docs-html/current/rtl/fgl/tfpgmap.html |
Revision as of 18:38, 13 November 2022
TFPGMap is part of the FGL
(Free Generics Library).
Example
Here is an example provided by forum user Remy Lebeau:
uses
..., fgl;
var
Dict: TFPGMap<string, integer>;
Value: Integer;
begin
Dict := TFPGMap<string, integer>.Create;
try
Dict.Add('VarName', 99);
...
Value := Dict['VarName'];
...
finally
Dict.Free;
end;
end;
IndexOfData
By default TFPGMap<>
does not provide a comparison for the Data type. So method IndexOfData will not find anything. You need to provide it by assigning the OnDataCompare event:
uses
StrUtils, fgl;
{$R *.lfm}
type
TMyTest = specialize TFPGMap<PtrInt, String>;
...
public
property MyTest: TMyTest read FMyTest write SetMyTest;
end;
...
function CompareStringFunc(const aData1, aData2: String): Integer;
begin
Result := AnsiCompareStr(aData1, aData2);
end;
procedure TForm1.FormCreate(Sender: TObject);
var
i: PtrInt = 0;
begin
FMyTest:= TMyTest.Create;
FMyTest.OnDataCompare := @CompareStringFunc;