LINQ和CASE灵敏度 [英] LINQ and CASE Sensitivity

问题描述

我有这个LINQ查询:

I have this LINQ Query:

TempRecordList = new ArrayList(TempRecordList.Cast<string>().OrderBy(s => s.Substring(9, 30)).ToArray());

它工作得很好，并且以一种准确的方式执行排序，但是与我想要的有点不同.在查询结果中，我看到这样的内容:

It works great and performs sorting in a way that's accurate but a little different from what I want. Among the the result of the query I see something like this:

彼得·布特(Palm-Bouter)，彼得
肖恩·帕尔默·约翰逊

Palm-Bouter, Peter
Palmer-Johnson, Sean

我真正需要的是对名称进行如下排序:

Whereas what I really need is to have names sorted like this:

肖恩·帕默·约翰逊
彼得·布伯特(Peter Palm-Bouter)

Palmer-Johnson, Sean
Palm-Bouter, Peter

基本上，我希望将'-'字符视为比该字符低的字符，以便稍后在升序搜索中显示包含该字符的名称.

Basically I want the '-' character to be treated as being lower than the character so that names that contain it show up later in an ascending search.

这是另一个例子.我得到:

Here is another example. I get:

雷金纳德·迪亚斯，
DiBlackley，安东

Dias, Reginald
DiBlackley, Anton

代替:

安东DiBlackley
雷迪纳尔·迪亚斯(迪亚斯)

DiBlackley, Anton
Dias, Reginald

如您所见，再次，由于大写字母'B'的处理方式，顺序被切换.

As you can see, again, the order is switched due to how the uppercase letter 'B' is treated.

所以我的问题是，我需要在LINQ查询中进行哪些更改以使其按我指定的顺序返回结果.任何反馈都将不胜感激.

So my question is, what do I need to change in my LINQ query to make it return results in the order I specified. Any feedback would be greatly appreaciated.

顺便说一句，我尝试使用 s.Substring(9，30).ToLower()，但这无济于事.

By the way, I tried using s.Substring(9, 30).ToLower() but that didn't help.

谢谢！

推荐答案

要自定义排序顺序，您将需要创建一个实现IComparer<string>接口的比较器类. OrderBy()方法将比较器作为第二个参数.

To customize the sorting order you will need to create a comparer class that implements IComparer<string> interface. The OrderBy() method takes comparer as second parameter.

internal sealed class NameComparer : IComparer<string> {
    private static readonly NameComparer DefaultInstance = new NameComparer();

    static NameComparer() { }
    private NameComparer() { }

    public static NameComparer Default {
        get { return DefaultInstance; }
    }

    public int Compare(string x, string y) {
        int length = Math.Min(x.Length, y.Length);
        for (int i = 0; i < length; ++i) {
            if (x[i] == y[i]) continue;
            if (x[i] == '-') return 1;
            if (y[i] == '-') return -1;
            return x[i].CompareTo(y[i]);
        }

        return x.Length - y.Length;
    }
}

这至少适用于以下测试用例:

This works at least with the following test cases:

var names = new[] {
    "Palmer-Johnson, Sean",
    "Palm-Bouter, Peter",
    "Dias, Reginald",
    "DiBlackley, Anton",
};

var sorted = names.OrderBy(name => name, NameComparer.Default).ToList();

// sorted:
// [0]: "DiBlackley, Anton"
// [1]: "Dias, Reginald"
// [2]: "Palmer-Johnson, Sean"
// [3]: "Palm-Bouter, Peter"

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