blocks|key|593177|text|也许我误解了你的问题。但是如果你不需要int。只需使用D即可。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|593178|public+class+B<T>+{+}
public+class+D+:+B<int>+{+}
public+class+A<T>+where+T+:+D+{+}
public+class+C+:+A<D>+{+}
public+class+Test1+{+public+class+test1+{+A<D>+t+=+new+C();++++}+}|code-block|syntax|javascript|593179|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Probably I missunderstood your question. But if you do not need int. Just use D. 

<pre><code>public class B&lt;T&gt; { }
public class D : B&lt;int&gt; { }
public class A&lt;T&gt; where T : D { }
public class C : A&lt;D&gt; { }
public class Test1 { public class test1 { A&lt;D&gt; t = new C(); } }
</code></pre>

blocks|key|2062160|text|声明A为：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2062161|public+class+A<T>+where+T+:+B<S>|code-block|syntax|javascript|2062162|应该可以工作，但我身上没有编译器，所以我不能肯定。|2062163|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Declare A as:

<pre><code>public class A&lt;T&gt; where T : B&lt;S&gt;
</code></pre>

Should work, but I don't have a compiler on me so I can't say for sure.

blocks|key|593195|text|A<D>+t+=+new+C();不会工作，因为您之前已经声明了A需要两个泛型参数。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|593196|您可以声明如下内容：|593197|class+A2<T>+:+A<T,+int>+{}|code-block|syntax|javascript|593198|然后(我认为)你可以实现A2<D>+t+=+new+C();，但我假设编译器足够聪明，能够意识到A2与C……可能不是。|593199|这是一个实验吗？看起来你可能很难弄清楚6个月后(甚至2个月后)这应该做什么。|593200|entityMap^0|0|H|0|0|0|C|I|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|V|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|W|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|X|8|@$9|Y|A|Z|B|C]]|D|@]|E|$]]|$1|O|3|P|5|6|7|10|8|@]|D|@]|E|$]]|$1|Q|3|-4|5|6|7|11|8|@]|D|@]|E|$]]]|R|$]]

<code>A&lt;D&gt; t = new C();</code> won't work because you have previously declared A to require two generic parameters. 

You could declare something like: 

<pre><code>class A2&lt;T&gt; : A&lt;T, int&gt; {}
</code></pre>

Then (I think) you could achieve <code>A2&lt;D&gt; t = new C();</code>, but I'm assuming that the compiler is smart enough to realize that A2 is compatible with C ... it may not be. 

Is this an experiment? Looks like you might have trouble figuring out what this is supposed to do 6 months from now (or even 2 months from now :)

blocks|key|2062220|text|下面是你的代码：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2062221|public+class+B<T>+{}
public+class+D+:+B<int>+{}
public+class+A<T,+S>+where+T+:+B<S>+{}
public+class+C+:+A<D,+int>+{}
public+class+Test1+{
++++public+class+test1+{
++++++++A<D,+int>+t+=+new+C();
++++}
}|code-block|syntax|javascript|2062222|下面是等价的代码：|2062223|public+class+B<T>+{}
public+class+D+:+B<int>+{}
public+class+A<U,+V>+where+U+:+B<V>+{}
public+class+C+:+A<D,+int>+{}
public+class+Test1+{
++++public+class+test1+{
++++++++A<D,+int>+t+=+new+C();
++++}
}|2062224|关键是A<U,+V>中的U是一个虚拟对象。当您将U替换为T+(将V替换为S)并编写A<T,+S>时，T在B<T>中不引用相同的T。这就是您必须使用C+:+A<D,+int>的原因。如果您只编写A<D>，编译器不知道(也不应该知道；请参阅我下面关于自由变量与非绑定变量的注释)，您希望在B<T>中为T使用int。|offset|length|style|CODE|2062225|2062226|所有的问题都来自类MyManager。如果我能在T+:+MyModel的地方做一些像:+MyManager<T>这样的事情，那就太好了。|blockquote|2062227|2062228|2062229|这是不可能的。MyModel未声明为类型。只有MyModel<T>是一个类型。更具体地说，它是一个无界泛型类型。当您指定一个类型参数(例如，MyModel<int>)时，它将是一个构造类型。|2062230|冒着进一步迷惑您的风险(在这个公认令人困惑的问题上)，它可能会帮助您阅读有关free+and+unbounded+variables的知识。|2062231|entityMap|0|LINK|mutability|MUTABLE|url|http://en.wikipedia.org/wiki/Free_variables_and_bound_variables^0|0|0|0|0|3|7|C|1|O|1|S|1|W|1|10|1|15|7|1E|1|1G|4|1R|1|21|D|2O|4|3Y|4|44|1|47|3|0|0|O|B|16|E|0|0|0|7|7|N|A|1Y|C|0|12|S|0|0^^$0|@$1|2|3|4|5|6|7|18|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|19|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|1A|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|1B|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|1C|8|@$M|1D|N|1E|O|P]|$M|1F|N|1G|O|P]|$M|1H|N|1I|O|P]|$M|1J|N|1K|O|P]|$M|1L|N|1M|O|P]|$M|1N|N|1O|O|P]|$M|1P|N|1Q|O|P]|$M|1R|N|1S|O|P]|$M|1T|N|1U|O|P]|$M|1V|N|1W|O|P]|$M|1X|N|1Y|O|P]|$M|1Z|N|20|O|P]|$M|21|N|22|O|P]|$M|23|N|24|O|P]|$M|25|N|26|O|P]]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|27|8|@]|9|@]|A|$]]|$1|R|3|S|5|T|7|28|8|@$M|29|N|2A|O|P]|$M|2B|N|2C|O|P]]|9|@]|A|$]]|$1|U|3|-4|5|6|7|2D|8|@]|9|@]|A|$]]|$1|V|3|-4|5|6|7|2E|8|@]|9|@]|A|$]]|$1|W|3|X|5|6|7|2F|8|@$M|2G|N|2H|O|P]|$M|2I|N|2J|O|P]|$M|2K|N|2L|O|P]]|9|@]|A|$]]|$1|Y|3|Z|5|6|7|2M|8|@]|9|@$M|2N|N|2O|1|2P]]|A|$]]|$1|10|3|-4|5|6|7|2Q|8|@]|9|@]|A|$]]]|11|$12|$5|13|14|15|A|$16|17]]]]

Here's your code:

<pre><code>public class B&lt;T&gt; {}
public class D : B&lt;int&gt; {}
public class A&lt;T, S&gt; where T : B&lt;S&gt; {}
public class C : A&lt;D, int&gt; {}
public class Test1 {
 public class test1 {
 A&lt;D, int&gt; t = new C();
 }
}
</code></pre>

Here's equivalent code:

<pre><code>public class B&lt;T&gt; {}
public class D : B&lt;int&gt; {}
public class A&lt;U, V&gt; where U : B&lt;V&gt; {}
public class C : A&lt;D, int&gt; {}
public class Test1 {
 public class test1 {
 A&lt;D, int&gt; t = new C();
 }
}
</code></pre>

The point is that the <code>U</code> in <code>A&lt;U, V&gt;</code> is a dummy. When you replace <code>U</code> with <code>T</code> (and <code>V</code> with <code>S</code>) and write <code>A&lt;T, S&gt;</code> the <code>T</code> does not refer to the same <code>T</code> in <code>B&lt;T&gt;</code>. This is why you must use <code>C : A&lt;D, int&gt;</code>. If you were to only write <code>A&lt;D&gt;</code> the compiler does not know (and nor should it; see my comment below on free versus unbound variables) that you want to use <code>int</code> for <code>T</code> in <code>B&lt;T&gt;</code>.

<blockquote>
 All the problem come from the class MyManager. If I was able to do something like <code>: MyManager&lt;T&gt;</code> where <code>T : MyModel</code> it's would be great.
</blockquote>

This is not possible. <code>MyModel</code> is not declared as a type. Only <code>MyModel&lt;T&gt;</code> is a type. More specifically, it is an unbounded generic type. When you specify a type argument (e.g., <code>MyModel&lt;int&gt;</code>) then it will be a constructed type.

At this risk of confusing you further (on this admittedly confusing issue), it might help you read about <a href="http://en.wikipedia.org/wiki/Free_variables_and_bound_variables" rel="nofollow noreferrer">free and unbounded variables</a>.

Here is an example :

<pre><code>public class B&lt;T&gt; {}
public class D : B&lt;int&gt; {}
public class A&lt;T, S&gt; where T : B&lt;S&gt; {}
public class C : A&lt;D, int&gt; {}

public class Test1
{
 public class test1
 {
 A&lt;D, int&gt; t = new C();
 }
}
</code></pre>

What I would like do to is in declaring class C, only say : <code>C : A&lt;D&gt;</code>. Why I need to repeat int ? Because int is already a part of D.

Same in the test1 method. I would like to write : <code>A&lt;D&gt; t = new C()</code>;

How, can I achieve that ?

<h1>UPDATE</h1>

Here with more realistic class names : 

<pre><code>public class MyModel&lt;T&gt; { }
public class MyTrueModel : MyModel&lt;int&gt; { }

public class MyManager&lt;T,S&gt; where T : MyModel&lt;S&gt; { }
public class MyTrueManager : MyManager&lt;MyTrueModel, int&gt; { }

public class Test1
{
 public class test1
 {
 MyManager&lt;MyTrueModel, int&gt; t = new MyManager&lt;MyTrueModel, int&gt;();
 }
}
</code></pre>

All the problem come from the class MyManager. If I was able to do something like : <code>MyManager&lt;T&gt; where T : MyModel</code> it'd would be great.

.Net c# Generic issue

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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下面是一个示例：public class B<T> {}public class D : B<int> {}public class A<T, S> where T : B<S> {}public class C : A<D, int> {}public class Test1{ public class tes...

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