无法理解如何使用泛型来做到这一点 [英] can't understand how to do this with generics
问题描述
如果我有一个通用类，例如：
公共类MyGroup< T> ：Collection< MyChildClass>
，我想从其中一个方法中将自己的引用传递给另一个类中的
跟随方法：
public void OnValidateChanged（MyGroup< MyChildClass> group）
我正在尝试：
_myReferenceToTheOtherClass.OnValidateChanged（this）;
错误信息是：
错误2参数''1'：无法转换'' MyNamespace.MyGroup< T>''
''MyNamespace.MyGroup<''MyNamespace.MyChildClass>
我已经尝试了所有可能的想法但是，不能破解它。我想b $ b猜我还不完全明白这个< T>东西。
谢谢
巴里莫斯曼
Hi, if I have a generic class such as:
public class MyGroup<T> : Collection<MyChildClass>
and from one of it''s methods I want to pass a reference to myself to the
following method in another class:
public void OnValidateChanged(MyGroup<MyChildClass> group)
I am trying:
_myReferenceToTheOtherClass.OnValidateChanged(this );
the error message is:
Error 2 Argument ''1'': cannot convert from ''MyNamespace.MyGroup<T>'' to
''MyNamespace.MyGroup<''MyNamespace.MyChildClass>
I have tried all the possibilities I can think of, but can''t crack it. I
guess I don''t fully understand this <T> stuff.
thanks
Barry Mossman
推荐答案
Barry Mossman < NO **** @ NoSpam.com> écritdansle message de news：
eT ******* *******@TK2MSFTNGP02.phx.gbl ...
|如果我有一个通用类，如：
|公共类MyGroup< T> ：Collection< MyChildClass>
|
|从其中一个方法我想将自己的引用传递给
|以下方法在另一个班级：
|
| public void OnValidateChanged（MyGroup< MyChildClass> group）
|
|我正在尝试：
|
| _myReferenceToTheOtherClass.OnValidateChanged（this）;
|
|错误信息是：
|
|错误2参数''1'：无法从''MyNamespace.MyGroup< T>''转换为
| ''MyNamespace.MyGroup<''MyNamespace.MyChildClass>
|
|我已经尝试了所有可以想到的可能性，但是不能破解它。我
|猜我不完全明白这个< T>东西。
< T>期望在MyGroup中绑定特定类型。除非你将
绑定到MyChildClass，否则你不能传递this。作为MyGroup< MyChaildClass>
除非您将T约束为MyChildClass。
公共类MyGroup< T> ：Collection< MyChildClass>其中T：MyChildClass
Joanna
-
Joanna Carter [TeamB]
顾问软件工程师
"Barry Mossman" <NO****@NoSpam.com> a écrit dans le message de news:
eT**************@TK2MSFTNGP02.phx.gbl...
| Hi, if I have a generic class such as:
| public class MyGroup<T> : Collection<MyChildClass>
|
| and from one of it''s methods I want to pass a reference to myself to the
| following method in another class:
|
| public void OnValidateChanged(MyGroup<MyChildClass> group)
|
| I am trying:
|
| _myReferenceToTheOtherClass.OnValidateChanged(this );
|
| the error message is:
|
| Error 2 Argument ''1'': cannot convert from ''MyNamespace.MyGroup<T>'' to
| ''MyNamespace.MyGroup<''MyNamespace.MyChildClass>
|
| I have tried all the possibilities I can think of, but can''t crack it. I
| guess I don''t fully understand this <T> stuff.
The <T> in MyGroup is expecting to be bound to a particular type. Unless you
bind it to MyChildClass, you cannot pass "this" as MyGroup<MyChaildClass>
unless you constrain the T to MyChildClass.
public class MyGroup<T> : Collection<MyChildClass> where T : MyChildClass
Joanna
--
Joanna Carter [TeamB]
Consultant Software Engineer
Joanna Carter [TeamB] ha scritto：
Joanna Carter [TeamB] ha scritto:
public class MyGroup< T> ：Collection< MyChildClass>其中T：MyChildClass
public class MyGroup<T> : Collection<MyChildClass> where T : MyChildClass
我很新在C＃（和泛型）但是...
....其中'与以下区别：
公共类MyGroup< MyChildClass> ：Collection< MyChildClass>
谢谢，
Giulio - Italia
I''m quite "new" in C# (and in generics) but...
....where''s the difference from:
public class MyGroup<MyChildClass> : Collection<MyChildClass>
Thanks,
Giulio - Italia
" Joanna Carter [ TeamB] QUOT; <乔**** @ not.for.spam>在消息中写道
news：Om ************** @ TK2MSFTNGP02.phx.gbl ...
"Joanna Carter [TeamB]" <jo****@not.for.spam> wrote in message
news:Om**************@TK2MSFTNGP02.phx.gbl...
< T>期望在MyGroup中绑定特定类型。除非你将它绑定到MyChildClass，否则你不能传递this。作为MyGroup< MyChaildClass>
除非您将T约束为MyChildClass。
公共类MyGroup< T> ：Collection< MyChildClass>其中T：MyChildClass
Joanna Carter [TeamB]
顾问软件工程师
The <T> in MyGroup is expecting to be bound to a particular type. Unless
you
bind it to MyChildClass, you cannot pass "this" as MyGroup<MyChaildClass>
unless you constrain the T to MyChildClass.
public class MyGroup<T> : Collection<MyChildClass> where T : MyChildClass
Joanna Carter [TeamB]
Consultant Software Engineer
感谢Joanna，很高兴看到TeamB也在这里运营< g>
我添加了where约束，但仍然从
后续行获取错误消息，例如：
MyGroup< MyChildClass> xxx = this;
参数''1'：不能隐式地将类型''MyNamespace.MyGroup< T>''转换为
''MyNamespace。 MyGroup<''MyNamespace.MyChildClass>
您有任何进一步的见解吗？
谢谢
Barry Mossman
Thanks Joanna, it is good to see TeamB operating over here as well <g>
I added the where constraint, but still get the error message from the
following line for example:
MyGroup<MyChildClass> xxx = this;
Argument ''1'': cannot implicitly convert type ''MyNamespace.MyGroup<T>'' to
''MyNamespace.MyGroup<''MyNamespace.MyChildClass>
Have you any further insight?
thanks
Barry Mossman
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