字符串中的Java字符到整数

Question

在检测到数字之前，一切似乎都是正确的。 数字1应保持为1.it显示为10 11 12 13 14 15 16 1 2 3 4 5 6 7 8 9 0

A = 10且B = 11，依此类推

如何更正以下错误

代码

String alpha = "ABCDEFG1234567890";

  for (int i = 0; i < alpha.length(); i++) {
            char c = alpha.charAt(i);
             int w = (int)c;
             System.out.println(w-55);
    }

输出

10 11 12 13 14 15 16 -6 -5 -4 -3 -2 -1 0 1 2 -7

Answer 1

您可以尝试Character.isDigit()方法。另请注意，您可以使用char将int投射到(int)c：

public static void main(String[] args) throws IOException
{
    String alpha = "ABCDEFG1234567890";

    for (int i = 0; i < alpha.length(); i++) {
        char c = alpha.charAt(i);

        if (Character.isDigit((c))) {
            System.out.println(c);
        } else {
            System.out.println((int)c - 55); // Cast to 'int'
        }
    }
}

<强> <子>输出：

10
11
12
13
14
15
16
1
2
3
4
5
6
7
8
9
0

Answer 2

String alpha = "ABCDEFG1234567890";

for (int i = 0; i < alpha.length(); i++) {
    char c = alpha.charAt(i);
    int w = (int)c;
    if (w >= 65) {
        System.out.println(w-55);
    } else {
        System.out.println(w-48);
    }
}

Answer 3

使用返回int的Character.digit(c, 10)

Answer 4

 public static void main(String args[]) throws FileNotFoundException
   {

     String alpha = "ABCDEFG1234567890";

  for (int i = 0; i < alpha.length(); i++) 
  {
            char c = alpha.charAt(i);
   if(c>='1' && c<='9')  
          {
          System.out.print(c); 
          }
   else
         {
             int w = (int)c;
             System.out.print(w-55);
         }
  }

  }

Answer 5

public static void main(String[] args) {
    String alpha = "ABCDEFG1234567890";

      for (int i = 0; i < alpha.length(); i++) {
                char c = alpha.charAt(i);
                int w;
                 if(Character.isDigit(c)){
                     w =Character.digit(c, 10);
                 }else{
                    w = (int)c;
                     w=w-55;
                 }
                 System.out.println(w);
        }
}