删除字符串C#的第一个和最后一个字符

Question

For an exercise on codewars I had to remove the first and last character of a string. After some fidling about I found a solution that works:

    public static string Remove_char(string s)
    {
      return s.Substring(1, s.Length - 2);   
    }

My question is why do I have to use -2 instead of -1 at the end of the return line when I only want to remove the last character?

Answer 1

因为第二个参数不是您想要子字符串的偏移量，它是所需子字符串的长度。

Answer 2

The Substring counts the length starting at the first index.

So if you remove the first character the string already has s.Length-1 . If you now want to remove the last character as well you need to use s.Length-2 .

Answer 3

数组索引从 0 开始，如果你跳到最后一个索引，那么你需要 s.Length-1，即数组的长度 - 1。所以你的问题是你需要删除最后一个字符，这就是为什么你添加了 s.Length-2

Answer 4

因为您想返回从初始字符串的第二个到倒数第二个字符的子字符串，即不是第一个（第 0 个字符）也不是最后一个（长度为 1 个字符）。