静态成员 [英] Static Members
问题描述
你好朋友
请检查下面的代码。
一个用C＃和另一个用VB .Net
在C＃我不能通过
实例变量访问静态属性，但在VB中我可以轻松完成。
错误是
无法访问静态成员''ClassInCS.ABC.MyInt''
带有实例引用;使用类型名称来限定它
而不是
有人可以解释为什么
与语言之间存在这样的差异吗？ />
VB的优势是什么？
或者它不适合OOP规则？
问候
Mark。
C＃Code
class MyClass {
[STAThread]
static void Main（string [] args）{
Console.WriteLine（ABC.MyInt）;
ABC a;
Console.WriteLine（ a.MyInt）; //错误
a =新ABC（）;
Console.WriteLine（a.MyInt）; //错误
}
}
类ABC {
private static int m_MyInt = 1;
public static int MyInt {
get {
return m_MyInt;
}
set {
m_MyInt = value;
}
}
}
VB代码
Sub Main（）
Console.WriteLine（XYZ.MyInt）
Dim x As XYZ
Console.WriteLine（x.MyInt）
x =新XYZ（）
Console.WriteLine（x.MyInt）
结束子
类XYZ
Public Const MyPConst As Integer = 2
私有共享m_MyInt为Int32 = 1
公共共享属性MyInt（）为Int32
获取
返回m_MyInt
结束获取
Set（ByVal Value As Int32）
m_MyInt =价值
结束套件
结束物业
结束班
可能会减少混乱。一个静态变量不属于
任何实例，而是属于类。
我认为VB.Net做了一些不同的事情，因为它需要像VB一样
而C＃是为.Net Framework设计的？
-
使用M2，Opera的革命性电子邮件客户端： http://www.opera.com/m2/
Mark< ma ** @ discussion.microsoft.com>写道：请检查下面的代码。
一个在C＃和VB中的其他.Net
在C＃中，我无法通过
访问静态属性实例变量，但在VB中我可以轻松完成。
为什么你认为*应该*能够通过
$ b访问静态属性$ b一个实例变量？
它使得它看起来像属性是一个实例属性，所以
可能会让读者感到困惑。这是Java，IMO的一个问题 - 并且
它导致很多人编写如下的愚蠢代码：
Thread.currentThread（） .sleep（5000）;
当他们真正意味着
Thread.sleep（5000）;
- 但是第一个版本看起来你可以在
特定线程上调用sleep（）来将其发送到睡眠状态。
基本上我将其视为VB.NET中的一个缺陷，而不是C＃中的缺陷。
-
Jon Skeet - < sk *** @ pobox.com>
http://www.pobox.com/~skeet
如果回复该团体，请不要给我发邮件
* Morten Wennevik< Mo ********** **@hotmail.com> scripsit：可能会让它不那么混乱。静态变量不属于任何实例，而是属于类。
在VB.NET中，静态变量属于/ all / instances（''Shared''）。
这在语义上是一个区别。
-
Herfried K 。瓦格纳[MVP]
< http://www.mvps.org/dotnet>
Hello Friends
Please check the code below.
One in C# and other in VB .Net
In C# I am not able to access a static property by an
instance variable, but in VB I can do it easily.
The Error is
Static member ''ClassInCS.ABC.MyInt'' cannot be accessed
with an instance reference; qualify it with a type name
instead
Can anybody explain why there is such a difference between
to language?
Is this advantage to VB??
Or it doesn''t fit in rule of OOP?
Regards
Mark.
C# Code
class MyClass{
[STAThread]
static void Main(string[] args){
Console.WriteLine(ABC.MyInt);
ABC a;
Console.WriteLine(a.MyInt); //ERROR
a = new ABC();
Console.WriteLine(a.MyInt); //ERROR
}
}
class ABC{
private static int m_MyInt = 1;
public static int MyInt{
get{
return m_MyInt;
}
set{
m_MyInt = value;
}
}
}
VB Code
Sub Main()
Console.WriteLine(XYZ.MyInt)
Dim x As XYZ
Console.WriteLine(x.MyInt)
x = New XYZ()
Console.WriteLine(x.MyInt)
End Sub
Class XYZ
Public Const MyPConst As Integer = 2
Private Shared m_MyInt As Int32 = 1
Public Shared Property MyInt() As Int32
Get
Return m_MyInt
End Get
Set(ByVal Value As Int32)
m_MyInt = Value
End Set
End Property
End Class
Probably to make it less confusing. A static variable doesn''t belong to
any instance, but rather to the class.
I think VB.Net does some things differently because it needs to be like VB
whereas C# was designed for .Net Framework?
--
Using M2, Opera''s revolutionary e-mail client: http://www.opera.com/m2/
Mark <ma**@discussions.microsoft.com> wrote:Please check the code below.
One in C# and other in VB .Net
In C# I am not able to access a static property by an
instance variable, but in VB I can do it easily.
Why do you think you *should* be able to access a static property via
an instance variable?
It makes it look like the property is an instance property, so would
possibly confuse the reader. This is one problem with Java, IMO - and
it''s led a lot of people to write silly code like:
Thread.currentThread().sleep(5000);
when they really mean
Thread.sleep(5000);
- but the first version makes it look like you could call sleep() on a
particular thread to send it to sleep.
Basically I view this as a flaw in VB.NET, not in C#.
--
Jon Skeet - <sk***@pobox.com>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too
* Morten Wennevik <Mo************@hotmail.com> scripsit:Probably to make it less confusing. A static variable doesn''t belong
to any instance, but rather to the class.
In VB.NET, a static variable belongs to /all/ instances (''Shared'').
That''s semantically a difference.
--
Herfried K. Wagner [MVP]
<http://www.mvps.org/dotnet>
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