速记有条件在C＃中类似“在'SQL关键字 [英] Shorthand conditional in C# similar to SQL 'in' keyword

问题描述

在C＃中有没有写这个简写方式：

In C# is there a shorthand way to write this:

public static bool IsAllowed(int userID)
{
    return (userID == Personnel.JohnDoe || userID == Personnel.JaneDoe ...);
}

我爱：

Like:

public static bool IsAllowed(int userID)
{
    return (userID in Personnel.JohnDoe, Personnel.JaneDoe ...);
}

我知道我还可以使用开关，但也有可能是50左右功能这样我不得不写（到ASP.NET移植传统的ASP网站），所以我想，让他们尽可能短。

I know I could also use switch, but there are probably 50 or so functions like this I have to write (porting a classic ASP site over to ASP.NET) so I'd like to keep them as short as possible.

推荐答案

这个怎么样？

public static class Extensions
{
    public static bool In<T>(this T testValue, params T[] values)
    {
    	return values.Contains(testValue);
    }
}

用法：

Usage:

Personnel userId = Personnel.JohnDoe;

if (userId.In(Personnel.JohnDoe, Personnel.JaneDoe))
{
    // Do something
}

我不能居功，但我也想不起来在那里我看到了它。所以，信用给你，匿名Internet陌生人。

I can't claim credit for this, but I also can't remember where I saw it. So, credit to you, anonymous Internet stranger.

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