用逗号拆分数组以分隔每个元素

Question

我有一个打印出来的输出：1 2 3 4 5
我希望输出为：1,2,3,4,5
当我打印最终数组时，它看起来像：System.out.println(D);
我应该添加什么以满足我的需要。
欢迎大家回答。

Answer 1

将(typeof x)替换为数组的元素类型（或者将此代码放在通用函数中以获得奖励积分，但它不适用于原始类型）：

StringBuilder out = (new StringBuilder());

boolean first = true;

for ((typeof x) x : D) {
  if (!first) { 
    out.append(",")
  }

  out.append(x.toString());

  first = false;
}

return out.toString();

Answer 2

您可以创建自己的方法来打印结果，例如这个：

    for (int i = 0; i < D.length; i++) {
        System.out.print(D[i]);
        if (i != D.length-1){
            System.out.print(",");
        }
    }

Answer 3

我认为您正在尝试用逗号而不是空格打印出一个数组。

for (int i = 0; i < arr.length() - 1; i++) {
    System.out.print(arr[i]);
    System.out.print(',');
}
System.out.println(arr[arr.length() - 1]);

Answer 4

你可以单独打印数组的元素，像这样：

String output = "";
//go through all elements in D
for (int i =0;i<D.length;i++){
    //add the Integer to the String
    output = output+i;
    //add , if not the last element
    if (i<D.length-1){
        output = output+",";
    }
}
//Print it out
System.out.println(output);

Answer 5

试试这个代码：

如果您的数据类型是整数数组：

int my_array={1,2,3,4,5};

for(int i=0; i < my_array.length; i++) {
    System.out.print(my_array[i] + ",");//this line will print the value with a coma (,)
}

如果你的数据类型是字符串；

String my_number="1 2 3 4 5";

for(int i=0; i < my_number.length; i++){
    if(my_number.toCharArray()[i]!=' ')
       System.out.print(my_number.toCharArray()[i]+",");
}

或者，

String my_number="1 2 3 4 5";
my_number = my_number.replace(' ', ',');//this method (replace) will replace all space(' ') by coma(',')
System.out.println(my_number);

Answer 6

为什么不简单地使用 Arrays.toString

public static String toString(int[] a) Returns a string representation of the contents of the specified array. The string representation consists of a list of the array's elements, enclosed in square brackets ("[]"). Adjacent elements are separated by the characters ", " (a comma followed by a space). Elements are converted to strings as by String.valueOf(int). Returns "null" if a is null. Parameters: a - the array whose string representation to return Returns: a string representation of a Since: 1.5

尝试

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

如果不需要空格，则可以 replaced 使用

System.out.println (Arrays.toString (D).replace(" ", ""));

用逗号拆分数组以分隔每个元素

Splitting an array with commas to separate each elemnt

java

arrays

element