c# - 了解字符串比较行为

我需要将一些字符串比较从vb转换为C#。 VB代码使用>和

[TestMethod]
public void TestMethod2()
{
    string originalCulture = CultureInfo.CurrentCulture.Name; // en-GB

    var a = "d".CompareTo("t");  // returns -1
    var b = "T".CompareTo("t");  // returns 1

    Assert.IsTrue(a < 0, "Case 1");
    Assert.IsTrue(b <= 0, "Case 2");
}

有人可以解释为什么b返回1。我目前的理解是，如果区分大小写，则“T”应按排序顺序(即-1)位于“t”之前。如果不区分大小写，则将相同，即0

(FYI .Net Framework 4.5.2)

很多thx

最佳答案

小写字母先于大写字母。
对于en-GB和InvariantCulture都是如此。

如果您想要类似ASCII的行为，则应指定其他的CompareOptions.Ordinal参数

请参阅以下内容:

Difference between InvariantCulture and Ordinal string comparison

C# sorting strings small and capital letters

repl.it上的示例代码:

using System;
using System.Globalization;
using System.Collections.Generic;

class MainClass
{
    public static void Main(string[] args)
    {

        //All the following case sensitive comparisons puts d before D
        Console.WriteLine("D".CompareTo("d"));
        Console.WriteLine(String.Compare("D", "d", false));
        Console.WriteLine(String.Compare("D", "d", false, CultureInfo.InvariantCulture));

        //All the following case sensitive comparisons puts capital D before small letter d
        Console.WriteLine(String.Compare("D", "d", CultureInfo.InvariantCulture, CompareOptions.Ordinal));

        //The following is case insensitive
        Console.WriteLine(String.Compare("D", "d", true));

        //The default string ordering in my case is d before D
        var list = new List<string>(new[] { "D", "d" });
        list.Sort();
        foreach (var s in list)
        {
            Console.WriteLine(s);
        }
    }
}

//Results on repl.it
//Mono C# compiler version 4.0.4.0
//
//1
//1
//1
//-32
//0
//d
//D

祝你好运

艾尔