Enum.GetNames（）会导致意想不到的才能与负枚举​​常量 [英] Enum.GetNames() results in unexpected order with negative enum constants

问题描述

我有以下枚举定义（在C＃）：​​

I have the following enum definition (in C#):

public enum ELogLevel
{
    General = -1,  // Should only be used in drop-down box in Merlinia Administrator log settings
    All = 0,       // Should not be used as a level, only as a threshold, effectively same as Trace
    Trace = 1,
    Debug = 2,
    Info = 3,
    Warn = 4,
    Error = 5,
    Fatal = 6,
    Off = 7        // Should not be used as a level, only as a threshold
}

现在，当我做了一个 Enum.GetNames（）这种类型我得到一个字符串数组，如预期9个元素，但秩序是一切，跟踪。 ..，关将军，这不是我所期待的。

Now, when I do an Enum.GetNames() on this type I get a string array with 9 elements as expected, but the order is All, Trace, ... , Off, General, which is not what I was expecting.

下面是枚举的MSDN 文档。 GetNames（）：

Here's the MSDN documentation for Enum.GetNames():

备注：返回值数组的元素是由排序   枚举常量的值。

"Remarks: The elements of the return value array are sorted by the values of the enumerated constants."

这是怎么回事呢？我可以改变我的计划采取这种功能性考虑，但那种我想知道为什么.NET是做什么它做。

What's going on here? I can change my program to take this "functionality" into account, but I'd kind of like to know why .NET is doing what it's doing.

推荐答案

这是既 GetNames（）中的已知错误和的GetValues​​（） 已报告这里，但最终得到关闭，不会解决：

This is a known bug with both GetNames() and GetValues() that was reported here, but ended up getting closed as won't fix:

是的，这种方法确实有它返回枚举值排序为无符号类型的数组（-2是0xFFFFFFFE和-1是0xFFFFFFFF在补，这就是为什么他们表现出了在列表的最后一个bug ），而不是返回值进行排序由他们签名的类型。

Yes, this method indeed has a bug where it returns the array of enum values sorted as unsigned-types (-2 is 0xFFFFFFFE and -1 is 0xFFFFFFFF in two's complement, that's why they are showing up at the end of the list) instead of returning values sorted by their signed-types.

不幸的是，我们不能改变的GetValues​​的排序顺序，因为我们将打破已写入依赖于当前的排序行为，所有现有的.NET程序[...]

Unfortunately, we cannot change the sort order of GetValues because we will break all existing .NET programs that have been written to depend on the current sorting behavior [...]

看起来你必须自己重新排序的值。

Looks like you'll have to reorder the values yourself.

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