C#中的此参数修饰符? [英] this parameter modifier in C#?

问题描述

我对以下代码片段感到好奇:

I'm curious about this code snippet:

public static class XNAExtensions
{
    /// <summary>
    /// Write a Point
    /// </summary>
    public static void Write(this NetOutgoingMessage message, Point value)
    {
        message.Write(value.X);
        message.Write(value.Y);
    }
    // ...
};

this 关键字在参数类型旁边是什么意思?即使在C#规范中，我似乎也找不到任何有关它的信息.

What does the this keyword mean next to the parameter type? I can't seem to find any information about it anywhere, even in the C# specification.

推荐答案

那是扩展方法.

语法意味着您可以像调用该方法一样将其视为NetOutgoingMessage类的成员:

The syntax means you can call the method as if it was a member of the NetOutgoingMessage class:

var msg = new NetOutgoingMessage();
msg.Write(somePoint);

这基本上是由编译器重写为:

This is basically rewritten by the compiler to:

var msg = new NetOutgoingMessage();
XNAExtensions.Write(msg, somePoint);

这只是很好的语法糖.

这篇关于C#中的此参数修饰符?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！