我可以将Class类型作为过程参数传递吗

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我想创建一个将某个类的所有名称作为字符串列表返回的函数。基于先前的解决方案/问题，我尝试对该代码进行失败

I want to create a function that returns all the names of a certain class as a string list. Based on the previous solution / question I tried to this code with no success

function GetClassElementNames (TObject ) : TStringlist ; var LCtx : TRttiContext; LMethod : TRttiMethod; begin try LCtx:=TRttiContext.Create; try // list the methods for the any class class for LMethod in LCtx.GetType(TObject).GetMethods do result.add(LMethod.Name); finally LCtx.Free; end; except on E: Exception do result.add (E.ClassName + ': ' + E.Message); end; end;

推荐答案

使用 TClass ，这是 TRttiContent.GetType（）所期望的。

您也没有分配填充前的结果。

You are also not allocating the Result before filling it.

尝试一下：

function GetClassElementNames(Cls: TClass) : TStringlist ; var LCtx : TRttiContext; LMethod : TRttiMethod; begin Result := TStringList.Create; try LCtx := TRttiContext.Create; try for LMethod in LCtx.GetType(Cls).GetMethods do Result.Add(LMethod.Name); finally LCtx.Free; end; except on E: Exception do Result.Add(E.ClassName + ': ' + E.Message); end; end;

var Methods: TStringList; begin Methods := GetClassElementNames(TSomeClass); try ... finally Methods.Free; end; end;

如果要传递对象实例而不是类类型，则可以包装 GetClassElementNames（）像这样：

If you want to pass in an object instance instead of a class type, you can wrap GetClassElementNames() like this:

function GetObjectElementNames(Object: TObject): TStringList; begin Result := GetClassElementNames(Object.ClassType); end;

这样说，返回一个新的TStringList对象不是一个好主意。如果调用方分配TStringList并将其传递给函数以进行填写，则更好，更灵活，例如：

With that said, it is not a good idea to return a new TStringList object. It is better, and more flexible, if the caller allocates the TStringList and passes it to the function to fill in, eg:

procedure GetClassElementNames(Cls: TClass; AMethods: TStrings); var LCtx : TRttiContext; LMethod : TRttiMethod; begin try LCtx := TRttiContext.Create; try for LMethod in LCtx.GetType(Cls).GetMethods do AMethods.Add(LMethod.Name); finally LCtx.Free; end; except on E: Exception do AMethods.Add(E.ClassName + ': ' + E.Message); end; end; { procedure GetObjectElementNames(Object: TObject; AMethods: TStrings); begin GetClassElementNames(Object.ClassType, AMethods); end; }

var Methods: TStringList; begin Methods := TStringList.Create; try GetClassElementNames(TSomeClass, Methods); ... finally Methods.Free; end; end;