The feature is named XML Documentation Comments and is documented here. It appears to have been modelled closely on the equivalent .net feature so you should be right at home with it. The documentation contains this example: /// <summary> Removes the specified item from the collection /// </summary> /// <param name=”Item”>The item to remove /// … Read more
This is not a bug, but “feature”: For a string, dynamic array, method pointer, or variant result, the effects are the same as if the function result were declared as an additional var parameter following the declared parameters. In other words, the caller passes an additional 32-bit pointer that points to a variable in which … Read more
Please have a look at closures. Delphi anonymous functions are closures. These are created within other functions and as such has access to the scope of that function. This is even so if the anonumous function is assigned to a function parameter that is called after the original function is called. (I will create an … Read more
You can use PathGetCharType function, PathCleanupSpec function or the following trick: function IsValidFilePath(const FileName: String): Boolean; var S: String; I: Integer; begin Result := False; S := FileName; repeat I := LastDelimiter(‘\/’, S); MoveFile(nil, PChar(S)); if (GetLastError = ERROR_ALREADY_EXISTS) or ( (GetFileAttributes(PChar(Copy(S, I + 1, MaxInt))) = INVALID_FILE_ATTRIBUTES) and (GetLastError=ERROR_INVALID_NAME) ) then Exit; if I>0 … Read more
TStringList is a descendant of TStrings. TStringList knows how to sort itself alphabetically. TStringList has an Objects property. TStringList doesn’t make your code incompatible with all previous versions of Delphi. TStringList can be used as a published property. (A bug prevents generic classes from being published, for now.)
Ok, my reaction is a bit late, but here’s a solution for the newer Delphi’s. It uses implicit class overloaders so that records of this type can be used as if they are TDateTime variables. TDateRec = record year,month,day,hour,minute,second,millisecond:word; class operator implicit(aDateRec:TDateRec):TDateTime; class operator implicit(aDateTime:TDateTime):TDateRec; // not needed class operator implicit(aDateRec:TDateRec):String; // not needed class … Read more
You don’t need to use external libraries to perform a JSONPath search. Example with Delphi 10 Seattle: uses System.JSON; procedure ParseJSonValue; var JSonValue:TJSonValue; st:string; Branch: string; begin st := ‘{“data”:{“results”:[{“Branch”:”ACCT590003″}]}}’; JsonValue := TJSonObject.ParseJSONValue(st); Branch := JsonValue.GetValue<string>(‘data.results[0].Branch’); JsonValue.Free; end;
Historical reasons, mostly. FillChar() dates back to the Turbo Pascal days and was used for such purposes. The name is really a bit of a misnomer because while it says FillChar(), it is really FillByte(). The reason is that the last parameter can take a char or a byte. So FillChar(Foo, SizeOf(Foo), #0) and FillChar(Foo, … Read more
You could use AnsiIndexText(const AnsiString AText, const array of string AValues):integer or MatchStr(const AText: string; const AValues: array of string): Boolean; (Both from StrUtils unit) Something like: Result := (AnsiIndexText(‘Hi’,[‘Hello’,’Hi’,’Foo’,’Bar’]) > -1); or Result := MatchStr(‘Hi’, [‘foo’, ‘Bar’]); AnsiIndexText returns the 0-offset index of the first string it finds in AValues that matches AText case-insensitively. … Read more
you can use the ZeroMemory procedure located in the Windows unit. var MyList : TListSignals; begin ZeroMemory(@Mylist,SizeOf(MyList)); end;