Visual Basic 中的共享类字段
我有一个类 MyClass，声明为 public，具有 Shared 方法 test()：
Public Class MyClass
Public Shared Function test()
Return "sdfg"
End Function
' snip other non-shared methods
End Class
这个 Class 是位于网站的 App_Code 目录中，并且似乎是可见的，因为我可以从任何网站脚本实例化该类的实例。
我的问题特别与访问 Shared 方法 test() 相关。为了使其正常工作，我在其中一个脚本的 Page_Load() 中有以下代码：
Sub Page_Load(ByVal Sender as Object, ByVal E as EventArgs)
Response.Write MyClass.test()
Dim myClassVar As MyClass = new MyClass()
myClassVar.nonSharedMethod()
End Sub
如果我注释掉 Response.Write MyClass.test()，一切正常很好，我可以使用 Class - 但是，尝试访问 Shared 方法时，我收到以下错误：
Local variable 'myClass' cannot be referred to before it is declared
有任何关于我做错了什么的指示吗？
I have a class, MyClass, declared as public, with a Shared method test():
Public Class MyClass
Public Shared Function test()
Return "sdfg"
End Function
' snip other non-shared methods
End Class
This Class is located in the App_Code directory of the website, and appears to be visible, as I can instantiate an instance of the Class from any of the sites scripts.
My issue relates specifically to accessing the Shared method test(). Trying to get this working, I have the following code in Page_Load() of one of the scripts:
Sub Page_Load(ByVal Sender as Object, ByVal E as EventArgs)
Response.Write MyClass.test()
Dim myClassVar As MyClass = new MyClass()
myClassVar.nonSharedMethod()
End Sub
If I comment out Response.Write MyClass.test(), everything works fine and I can use the Class - however, trying to access the Shared method, I get the following error:
Local variable 'myClass' cannot be referred to before it is declared
Any pointers as to what I am doing wrong?
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我猜测，在出于发布目的而混淆此代码时，您掩盖了这样一个事实：您在页面加载中也声明了一个名为
MyClass的变量（这就是错误的基本含义） ）。Visual Basic 是一种不区分大小写的语言。将变量声明为
myClass与将其声明为MYCLASS或myclass相同，并且行MyClass.test() 会将名称MyClass解析为该变量 - 正如错误所示，该变量尚未声明。I'm guessing that in obfuscating this code for posting purposes, you've masked the fact that you have a variable with the name
MyClassalso declared in your page load (that is what the error is basically saying).Visual Basic is a case insensitive language. Declaring your variable as
myClassis the same as declaring it asMYCLASSormyclass, and the lineMyClass.test()will be resolving the nameMyClassto that variable - which as the error indicates, hasn't been declared yet.