方法的内部/嵌套范围 [英] Inner/Nested Scope in Methods

问题描述

我是一位C＃开发人员，长期从事该语言的开发。

I am a C# developer who has been working with the language for a long time.

我想知道为什么语言允许嵌套/内部作用域。

I am wondering why the langauge allows nested/inner scopes for functions.

以下是我的意思的示例：

Here is an example of what I mean:

        public int InnerScopeMethod()
    {
        int i = 10;

        //Inner Scope
        {               
            int j = 100;//j will not work outside of the scope.
            i *= j;
        }//Scope Ends Here

    //j = 10 /// This Will Cause Error.
        return i;
    }

如您所见，方法主体具有匿名或未命名范围，它是在C＃4中是合法的。

As you can see the method body has an anonymous or unnamed scope and it is legal in C# 4.

我想知道为什么在这里吗？

I want to know why is it here? Is this just for providing small scopes for variables or it has other uses?

任何帮助将不胜感激。

推荐答案

（通常至少）没有必要在C＃中执行此操作，但是随后（如布兰登·摩尔所说），为什么不呢？

It (usually at least) isn't necessary to do this in C#, but then (as Brandon Moore said), why not?

一个原因可能是某些变量仅在有限的时间内有效，然后将其放入范围内，可以确保没有人以后会意外使用它们。

One reason could be that certain variables only have a limited time where they are valid, and by putting that variable inside a scope, you make sure that noone can accidentally use them later.

此外，C＃基于C，这种构造非常有用。在C语言中，变量只能在作用域的开始处声明，因此，如果您只需要在一个地方使用一个临时变量（例如循环索引），则可以使用长方法来完成类似您编写的操作。

Additionally, C# is based on C, where this construct is very useful. In C, variables can only be declared at the start of a scope, so something like what you wrote can be done in long methods if you only need a temporary variable at one place (ex. a loop index).

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