c# - ToLower 与 ToLowerInvariant

Question

我只是在寻找这两种方法产生不同结果的任何例子。首先，我访问msdn page , 并从中运行代码并稍作更改

using System;
using System.Globalization;
using System.Linq;

class Program
{
    static void Main()
    {
        string[] words = { "Tuesday", "Salı", "Вторник", "Mardi", 
                         "Τρίτη", "Martes", "יום שלישי", 
                         "الثلاثاء", "วันอังคาร" };
        Console.BufferHeight = 1000;
        var test = CultureInfo.GetCultures(CultureTypes.AllCultures)
                              .Select(ci =>
                                      {
                                          string[] wordsToLower = words.Select(x => x.ToLower(ci)).ToArray();
                                          string[] wordsToLowerInvariant = words.Select(x => x.ToLowerInvariant()).ToArray();
                                          return new
                                                 {
                                                     Culture = ci,
                                                     ToLowerDiffers = !wordsToLower.SequenceEqual(wordsToLowerInvariant)
                                                 };
                                      })
                              .ToArray();
        foreach (var x in test)
        {
            Console.WriteLine("Culture {0}, ToLower and ToLowerInvariant produces different results: {1}", x.Culture, x.ToLowerDiffers);
        }
        Console.WriteLine();
        Console.WriteLine("Difference exists for any ToLower call: {0}", test.Any(x => x.ToLowerDiffers));
    }
}

但这里我遇到了一个问题:此代码在所有现有文化中为 ToLower 和 ToLowerInvariant 调用生成相同的输出。

那么问题是:是否有任何字符串会为此测试产生不同的结果？

Answer 1

试试土耳其语点缀 İ:

var culture = new CultureInfo("tr-TR");

string test = "İ";

if (test.ToLower(culture) == test.ToLowerInvariant())
    Console.WriteLine("Same");
else
    Console.WriteLine("Different"); // Prints this!