Question

我正在循环将数据写入字符串数组。但我想要的是我创建了另一个循环，我将循环遍历values的数据和amount一样多，但我想对如何这样做有一些指导。

String[] s = new String[20];
String[] values = { "A", "B", "C", "D" };
final int amount = 2;

for (int i = 0; i < s.length; i++) {
    s[i] = String.format("%s%04d", values[0], i); //TODO create another loop?
}
System.out.println(Arrays.toString(s));

首选输出应为：

A0000, A0001, B0002, B0003, C0004, ...

实际输出是：

A0000, A0001, A0002, A0003, A0004, ...

Answer 1

问题：你的循环错误。

试试这个：

 public static void main(String[] args) {

          int k=0;
          String[] s = new String[20];
            String[] values = { "A", "B", "C", "D" };
            final int amount = 2;
            for (int i = 0; i < values.length; i++){

                 for (int j = 0; j < amount; j++){ //data of values as much as amount
                  s[k++] = String.format("%s%04d", values[i], k); 
                 }
            }
            System.out.println(Arrays.toString(Arrays.copyOf(s,k)));
     }

输出：

[A0001, A0002, B0003, B0004, C0005, C0006, D0007, D0008]

Answer 2

你需要有2个循环来遍历实际的values数组，然后另一个循环是amount（次数）。

试试这个

    List<String> a = new ArrayList<String>();
    String[] values = { "A", "B", "C", "D" };
    final int amount = 2;
    int incrementVariable = 0;
    for (int i = 0; i < values.length; i++){
        for(int j = 0; j< amount; j++){
            a.add(String.format("%s%04d", values[i], incrementVariable)); 
            incrementVariable +=1;
        }
    }
    System.out.println(a);
}

输出：

[A0000, A0001, B0002, B0003, C0004, C0005, D0006, D0007]

Answer 3

我喜欢while循环更好：）

String[] s = new String[10];
String[] values = {"A", "B", "C", "D"};
final int amount = 2;

for (int i = 0; i < values.length; ++i) {
    int buffer = 0;
    while(buffer <= amount) {
        int index = i * amount + buffer;
        s[index] = values[i] + String.format("%04d", index);
        buffer++;
    }
}

System.out.println(Arrays.toString(s));

[A0000，A0001，B0002，B0003，C0004，C0005，D0006，D0007，D0008，null]

循环创建自定义字符串

3 个答案: