C# 返回错误的整数值

Question

我正在尝试 return 基于用户输入的索引，输入只有 2 个字符，例如 a1、b2、c3...

public int returnInt(string x)
        {
            if (x == "a")
                return 0;
            else if (x == "b")
                return 1;
            else if (x == "c")
                return 2;
            else if (x == "d")
                return 3;
            else if (x == "e")
                return 4;
            else if (x == "f")
                return 5;
            else if (x == "g")
                return 6;
            else if (x == "h")
                return 7;
            else if (x == "1")
                return 0;
            else if (x == "2")
                return 1;
            else if (x == "3")
                return 2;
            else if (x == "4")
                return 3;
            else if (x == "5")
                return 4;
            else if (x == "6")
                return 5;
            else if (x == "7")
                return 6;
            else if (x == "8")
                return 7;
            return 0;
        }

And this is where i use the method:

var toMove = myButtonArray[returnInt(totxt.Text.Substring(0)), returnInt(totxt.Text.Substring(1))];

the method works fine for the second substring, but it doesn't work for the first substring(0). Can anyone help me about this? When I type a1, program should return to 1 and 1 but it only returns 0 for the first substring.

Answer 1

让我们用单个字符，而不是字符串s:

public int returnInt(char x) =>
    x >= 'a' && x <= 'h' ? x - 'a'
  : x >= '1' && x <= '8' ? x - '1'
  : 0;

然后你可以输入：

var toMove = myButtonArray[returnInt(totxt.Text[0]), returnInt(totxt.Text[1])];

请注意，我们得到的是 0th 和 1st char，而不是 string

Answer 2

由于您的输入字符串始终只有 2 个字符，并且您想将它们用作二维数组的索引，因此您需要将代码更改为以下内容：

var toMove = myButtonArray[returnInt(totxt.Text.Substring(0,1)), 
                           returnInt(totxt.Text.Substring(1,1))];

这样你就是说 String.Substring 函数一次 return 1 个字符，并提到起始索引作为第一个输入参数。

C# 返回错误的整数值

C# Returning Wrong Integer Value

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