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遍历数组-仅第一索引打印

[英]looping through array - only first index printing

I want to loop through an array and print any values that are not null, here is the code I am trying to use: 我想遍历一个数组并打印任何不为null的值,这是我尝试使用的代码:

for (int i = 0; i < 10; i++) {
  if (studentNamesArray[i] != null) {
    studentFound = true;
    System.out.println("Which student would you like to delete?");
    System.out.println(i + ": " + studentNamesArray[i]);
    int studentChoice = input.nextInt();
  }
}

Array: 阵:

static String[] studentNamesArray = new String[10];

The problem is that it is only printing out index[0] . 问题在于它仅打印出index[0] How can I fix this? 我怎样才能解决这个问题?

EDIT: 编辑:

Here is my full code: 这是我的完整代码:

  static void deleteStudent() {
    boolean studentFound = false;
    for (int i = 0; i < 10; i++) {
      if (studentNamesArray[i] != null) {
        studentFound = true;
        System.out.println("Which student would you like to delete?");
        System.out.println(i + ": " + studentNamesArray[i]);
      }
        int studentChoice = input.nextInt();
        for (i = 0; i < 10; i++) {
        for (i = studentChoice + 1; i < studentNamesArray.length; i++) {
          studentNamesArray[i - 1] = studentNamesArray[i];
        }
        nameArrayCount = nameArrayCount - 1;
        studentNamesArray[studentNamesArray.length - 1] = null;
        for (i = studentChoice + 1; i < 9; i++) {
          for (int y = 0; y < 3; y++) {
            studentMarksArray[i - 1][y] = studentMarksArray[i][y];
          }
        }
        markArrayCount = markArrayCount - 1;
        for (int y = 0; y < 3; y++) {
          studentMarksArray[9][y] = 0;
        }
      }
    }
    if (!studentFound) {
      System.out.println("There are no students stored");
    }
  }

Use the for-loop only to print the students names. 仅使用for循环打印学生姓名。 And read the studentChoice once after you printed all the students. 打印studentChoice所有学生后,阅读一次studentChoice Otherwise it waits for input after printing the studentNamesArray[0] 否则,在打印studentNamesArray[0]之后等待输入

System.out.println("Which student would you like to delete?");
for (int i = 0; i < 10; i++) {
  if (studentNamesArray[i] != null) {
    studentFound = true;
    System.out.println(i + ": " + studentNamesArray[i]);
  }
}
int studentChoice = input.nextInt();

确保数组的内容不为空,否则它们不会打印出来

Only reason I can see here, other elements should be null . 我在这里看到的唯一原因是,其他元素应该为null You can make sure it as follows 您可以确保如下

 for (int i = 0; i < 10; i++) {
   if (studentNamesArray[i] != null) {
      studentFound = true;
      System.out.println("Which student would you like to delete?");
      System.out.println(i + ": " + studentNamesArray[i]);
      int studentChoice = input.nextInt();// you need to check this 
     }else{
      System.out.println(i + ": " + studentNamesArray[i]);
     }
   }

But may be there is another reason. 但是可能还有另一个原因。 If input.nextInt() is take from Scanner , your program will wait there for a user input. 如果input.nextInt()来自Scanner ,则程序将在那里等待用户输入。 Then you have to provide that input to continue. 然后,您必须提供该输入才能继续。 Make sure those things. 确保这些东西。

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