使用“with”创建的引用对象实例在德尔福 [英] Reference object instance created using "with" in Delphi

问题描述

有没有办法引用使用with语句创建的对象实例？

示例：

  with TAnObject.Create do 
 begin 
 DoSomething（instance）; 
结束
  

其中DoSomething将使用实例引用，就像您将一个实例从变量声明的引用传递给对象创建。

示例：

  AnObject：= TAnObject.Create ; 
  

谢谢。

解决方案

嗯，你可以使用这样的方法：

  //实现：
 
键入
 TSimpleMethod =对象的过程; 
 
函数GetThis（const pr：TSimpleMethod）：TObject; 
 begin 
结果：= TMethod（pr）.Data; 
结束
 
 //用法：
 
与TStringList.Create do 
 try 
 CommaText：='1,2,3,4,5,6， 7,8,9,0'; 
 ShowText（TStringList（GetThis（Free）））; 
终于
免费; 
结束
  

或类助手：

 键入
 TObjectHelper =类助手对于TObject 
 private 
函数GetThis：TObject;一致; 
 public 
属性This：TObject读取GetThis; 
结束
 
 ... 
 
函数TObjectHelper.GetThis：TObject; 
 begin 
结果：=自我; 
结束
  

但实际上，以前的回复是正确的：你最好忘记with语句。 p>

is there a way to reference an object instance that is created using the "with" statement?

Example:

with TAnObject.Create do
begin
  DoSomething(instance);
end;

Where DoSomething would use the instance reference as if you were passing an instance from a variable declared reference to the object created.

Example:

AnObject := TAnObject.Create;

Thanks.

解决方案

Well, you can use such approach:

// implement:

type
  TSimpleMethod = procedure of object;

function GetThis(const pr: TSimpleMethod): TObject;
begin
  Result := TMethod(pr).Data;
end;

// usage:

  with TStringList.Create do
  try
    CommaText := '1,2,3,4,5,6,7,8,9,0';
    ShowText(TStringList(GetThis(Free)));
  finally
    Free;
  end;

or class helpers:

type 
  TObjectHelper = class helper For TObject
  private
    function GetThis: TObject; Inline;
  public
    property This: TObject read GetThis;
  end;

...

function TObjectHelper.GetThis: TObject;
begin
  Result := Self;
end;

But, actually, previous replies are correct: you should better forget about "with" statement.

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