铸造问题 [英] Casting issue
问题描述
嘿伙计
i有这样的设置：
界面IMyInt //界面
class myClass：IMyInt // myCLass意识到这个界面
class myOtherClass：myClass //一个继承自该父级的类
绑定到界面
class myClassA：myOtherClass //继承
的类然后在我的代码中我这样做：
myClassA obj =（ myClassA）myOtherClass; //< ----并抛出一个不能
将myOtherCLass转换为myCLassA错误
myOtherClass没有私有变量。为什么不能施展？
Hey guys
i have a set up like this:
Interface IMyInt //interface
class myClass : IMyInt //myCLass realises that interface
class myOtherClass : myClass // a class that inherits from that parent
bound to the interface
class myClassA : myOtherClass //a class that inherits
then in my code i do this:
myClassA obj = (myClassA)myOtherClass; //<----and this throws a cannot
cast myOtherCLass to myCLassA error
myOtherClass has no private variables. Why can''t it cast?
推荐答案
我有这样的设置：
i have a set up like this:
>
界面IMyInt //界面
class myClass：IMyInt // myCLass意识到这个界面
class myOtherClass：myClass //继承自该界面的
父级的类
class myClassA：myOtherClass //继承的类
然后在我的代码中我这样做：
myClassA obj =（myClassA）myOtherClass; //< ----并抛出一个
无法将myOtherCLass转换为myCLassA错误
myOtherClass没有私有变量。为什么不能演员？
>
Interface IMyInt //interface
class myClass : IMyInt //myCLass realises that interface
class myOtherClass : myClass // a class that inherits from that
parent bound to the interface
class myClassA : myOtherClass //a class that inherits
then in my code i do this:
myClassA obj = (myClassA)myOtherClass; //<----and this throws a
cannot cast myOtherCLass to myCLassA error
myOtherClass has no private variables. Why can''t it cast?
这实际上是您使用的代码吗？如果是这样，你就不能施放类名，
你只能施放一个类的实例。所以，这段代码是非法的：
myClass obj =（myClassA）myOtherClass;
但是，这段代码应该有效：
myOtherClass instance = new myOtherClass（）;
myClass obj =（myClassA）实例;
最好的问候，
Dustin Campbell
Developer Express Inc.
Is this actually the code your using? If so, you can''t cast a class name,
you can only cast an instance of a class. So, this code is illegal:
myClass obj = (myClassA)myOtherClass;
But, this code should work:
myOtherClass instance = new myOtherClass();
myClass obj = (myClassA)instance;
Best Regards,
Dustin Campbell
Developer Express Inc.
AHH！对不起，我在我的例子中犯了一个错误。是的，这是一个
的实例。
好的更正：
i有这样的设置：
界面IMyInt //界面
class myClass：IMyInt // myCLass意识到这个界面
class myOtherClass：myClass //继承自该父级的类
绑定到接口
class myClassA：myOtherClass //继承的类
然后在我的代码中我这样做：
myClassA obj =（myClassA）some_Instance_of_myOtherClass; //< ----并且这个
抛出一个无法将myOtherCLass转换为myCLassA错误
myOtherClass没有私有变量。为什么不能演员？
既然你说它应该演员我认为你看到我的上面的系数是正确的。所以
它还能做什么呢？我唯一的另一件事就是myClass与myClassA一样，是b $ b可序列化的。这会导致问题/我不明白为什么？
但是我不明白为什么这也不会工作。
AHH! Sorry i made a mistake in my example. Yes that was meant to be an
instance.
Ok corrected:
i have a set up like this:
Interface IMyInt //interface
class myClass : IMyInt //myCLass realises that interface
class myOtherClass : myClass // a class that inherits from that parent
bound to the interface
class myClassA : myOtherClass //a class that inherits
then in my code i do this:
myClassA obj = (myClassA)some_Instance_of_myOtherClass; //<----and this
throws a cannot cast myOtherCLass to myCLassA error
myOtherClass has no private variables. Why can''t it cast?
Since you said it should cast i presume you see my above coe as right. So
what else could it be? The only other thing i have is that the myClass is
serialisable as is the myClassA. Would that cause an issue/ i don''t see why?
But then i don''t get why this wont work either.
AHH！对不起，我在我的例子中犯了一个错误。是的，这是一个
AHH! Sorry i made a mistake in my example. Yes that was meant to be an
实例。
好的更正：
i有这样的设置：
界面IMyInt //界面
class myClass：IMyInt // myCLass实现界面
class myOtherClass：myClass //继承自
父级的类绑定到接口
class myClassA： myOtherClass //继承
的类然后在我的代码中我这样做：
myClassA obj =（myClassA）some_Instance_of_myOtherClass; //< ----和
这会抛出一个无法将myOtherCLass转换为myCLassA错误
myOtherClass没有私有变量。为什么不能演员？
instance.
Ok corrected:
i have a set up like this:
Interface IMyInt //interface
class myClass : IMyInt //myCLass realises that interface
class myOtherClass : myClass // a class that inherits from that
parent bound to the interface
class myClassA : myOtherClass //a class that inherits
then in my code i do this:
myClassA obj = (myClassA)some_Instance_of_myOtherClass; //<----and
this throws a cannot cast myOtherCLass to myCLassA error
myOtherClass has no private variables. Why can''t it cast?
实际上，我也没想过我的代码。变量
需要是要投射的myClassA的实例。像这样：
myOtherClass instance = new myClassA（）;
myClassA obj =（myClassA）实例;
最诚挚的问候，
Dustin Campbell
Developer Express Inc.
Actually, I hadn''t thought my code through very well either. The variable
needs to be an instance of myClassA to cast. Like this:
myOtherClass instance = new myClassA();
myClassA obj = (myClassA)instance;
Best Regards,
Dustin Campbell
Developer Express Inc.
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