delphi 函数过程类型 委托...？
<div id="cnblogs_post_body">算是一种减少单元之间的引用的方法类似委托
<div class="cnblogs_code" >http://images.cnblogs.com/OutliningIndicators/ContractedBlock.gifhttp://images.cnblogs.com/OutliningIndicators/ExpandedBlockStart.gifView Code <div id="cnblogs_code_open_8f11664e-2229-4d28-8cb2-c29de8139342" class="cnblogs_code_hide"> 1 unit Unit5; 2 3 interface 4 5 uses System.Classes, System.SysUtils, Vcl.Dialogs; 6 7 type 8 // 声明过程类型 9 TObjFuns = procedure(const str1, str2: string) of object;10 11 IFormattedNumber = interface12 ['{19AE4E57-A022-45B1-AA42-43FF5142D685}']13 function FormattedString: string;14 function GetName: string;15 end;16 17 TFormattedInteger = class(TInterfacedObject, IFormattedNumber)18 private19 FValue: Integer;20 public21 // 声明过程变量22 FPro: TObjFuns;23 constructor Create(AValue: Integer);24 destructor Destroy; override;25 function FormattedString: string;26 function GetName: string;27 procedure DoDelegate(str1, str2: string);28 end;29 30 TFormattedHexInteger = class(TFormattedInteger, IFormattedNumber)31 destructor Destroy; override;32 function FormattedString: string;33 function GetName: string;34 end;35 36 implementation37 38 { TFormattedInteger }39 40 constructor TFormattedInteger.Create(AValue: Integer);41 begin42 inherited Create;43 DoDelegate('TFormattedInteger', 'Destroy');44 FValue := AValue;45 end;46 47 destructor TFormattedInteger.Destroy;48 begin49 DoDelegate('TFormattedInteger', 'Destroy');50 inherited Destroy;51 end;52 53 procedure TFormattedInteger.DoDelegate(str1, str2: string);54 begin55 // 使用过程变量56 if Assigned(FPro) then57 FPro(str1, str2);58 end;59 60 function TFormattedInteger.FormattedString: string;61 begin62 Result := 'This integer is' + IntToStr(FValue);63 end;64 65 function TFormattedInteger.GetName: string;66 begin67 Result := 'TFormattedInteger.GetName';68 end;69 70 { TFormattedHexInteger }71 72 destructor TFormattedHexInteger.Destroy;73 begin74 DoDelegate('TFormattedHexInteger', 'Destroy');75 inherited Destroy;76 end;77 78 function TFormattedHexInteger.FormattedString: string;79 begin80 Result := 'The hex integer is $' + IntToHex(FValue, 4);81 end;82 83 function TFormattedHexInteger.GetName: string;84 begin85 Result := 'TFormattedHexInteger.GetName';86 end;87 88 end.
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