对.net 2.0失望啊失望啊失望啊失望啊失望啊

刚听到泛型啊（自以为能用上C++的模版功能了），操作符重载啊，类型转换重载啊，我是那个激动啊兴奋啊，心想.net的语法终于拨云见日可以和c++媲美啦。哪知道 一用才发现~~~~~~

写个类叫TestClass

Public Shared Widening Operator CType(ByVal tc As TestClass) As String
return "爽爽爽"
End Operator

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做个测试
dim s as string
dim tc as new TestClass
s=tc

编译pass,执行pass
爽了一把

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dim s as string
dim obj as object
dim tc as new new TestClass
obj=tc
s=obj

编译通过
执行
Unhandled Exception: System.InvalidCastException: Conversion from type 'TestClas
s' to type 'String' is not valid.
at Microsoft.VisualBasic.CompilerServices.Conversions.ToString(Object Value)

操！！Conversion from type 'TestClass' to type 'String' is not valid
明明可以转换，却说无法从TestClass转为String，睁眼说瞎话啊
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受了一个小打击，算了，去那个被宣传的神乎其神的泛型上找点安慰吧
创建泛型函数
public sub ShowItem(of ItemType)(byval Item as ItemType)
dim s as string
s=item
console.writeline(s)
end sub

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dim tc as new TestClass
ShowItem(tc)

编译：C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\a.vb(21) : error BC30311: Value of
type 'ItemType' cannot be converted to 'String'.

s=item
~~~~
晕，第一次玩就受打击，Value of type 'ItemType' cannot be converted to 'String'.看来想把不知类型的东东转化为某个类型是不可能的了，即使你重载了装换。

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还是玩玩操作符重载吧

Public Shared Operator >(byval a as TestClass,byval b as TestClass) as Boolean
return true
end Operator


Public Shared Operator <(byval a as TestClass,byval b as TestClass) as Boolean
return false
end Operator

------------------------------------------------------------------------------------
因为受了刚才的打击，不敢随便玩泛型了
写个简单的
sub Test(byval a as object,b as object)
console.writeline(ctype(a,string))
end sub

dim a as new TestClass
dim b as new TestClass
Test(a,b)
编译pass，运行pass，不容易，那个操作重载的功能，看来还是有用的
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被鼓励了一次，还是不能忘了那个泛型老大啊

public sub Test(of ItemType)(byval a as ItemType,byval b as ItemType)
console.writeline(a>b)
end sub

这种写法充分体现了模版语法的优势，你可以写个容器，里面放各种类型的东西，同时还可以对其进行排序，比较大小的操作…………（题外话能不能少一点啊~~~~）

OKOK，编译！！！！！！！！！！！！！！
C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\a.vb(35) : error BC30452: Operator
'>' is not defined for types 'ItemType' and 'ItemType'.
我靠，这都通不过，本人当时顿时傻了5秒钟



Object都可以过，泛型居然就不行，微软该不会这么弱吧~~~
为了证明我的想法，把泛型函数改了一下
public sub Test(of ItemType)(byval a as ItemType,byval b as ItemType)
dim oa ,ob as object
oa=a
ob=b
console.writeline(a>b)
end sub
本函数简直就是弱智写的，不过我就当一次弱智好了
编译pass，执行pass
晕泛型本来就是用来提高效率，避免值类型转换为引用类型的装箱操作，如果要这么写，那还有P个优势啊~~~~~

我就测试了这几项，这个net2.0的框架还是从windows update上更新下来的，我只能说好伤心啊，难道是我期望太高了嘛？？？~~~~