在Arraylist中刪除對象

這裏我的問題是，當我在數組中有2個對象時，它會循環2x，然後請求另一個「你確定要刪除它嗎？」。無法弄清楚我的循環。這裏是代碼：在Arraylist中刪除對象

for (Iterator<Student> it = student.iterator(); it.hasNext();) { 

    Student stud = it.next(); 
    do { 
     System.out.print("Are you sure you want to delete it?"); 
     String confirmDelete = scan.next(); 

     ynOnly = false; 

     if (confirmDelete.equalsIgnoreCase("Y") 
       && stud.getStudNum().equals(enterStudNum2)) { 
      it.remove(); 
      System.out.print("Delete Successful"); 
      ynOnly = false; 
     } else if (confirmDelete.equalsIgnoreCase("N")) { 
      System.out.print("Deletion did not proceed"); 
      ynOnly = false; 
     } else { 
      System.out.println("\nY or N only\n"); 
      ynOnly = true; 
     } 
    } while (ynOnly == true); 

}

來源

2014-10-05 Pun Pun

你應該明白之間的差別了'做/ while'循環和'while'循環:) – nem035 2014-10-05 04:47:21

@Trafalgar法：對於兩個對象的名單，你應該看到「你確定...？」兩次，並且「刪除成功」兩次，假設您爲循環的每次迭代按'y'/'Y'，並且'stud.getStudNum（）。equals（enterStudNum2）'爲'true'。你的輸出是什麼？ – Voicu 2014-10-05 04:51:19

@Voicu輸出是這樣的.. 刪除成功您確定要刪除它嗎？它要求另一個確認，而不是隻有一個確認 – 2014-10-05 06:04:56

它是因爲有兩個循環在那裏。在ynOnly的值變爲false但外循環仍然繼續之後，內循環終止。您可能要像that--

for (Iterator<Student> it = student.iterator(); it.hasNext();) { 

Student stud = it.next(); 
if(!stud.getStudNum().equals(enterStudNum2)) 
      continue;       //you want only that student to be deleted which has enterStudNum2 so let other record skip 
do { 
    System.out.print("Are you sure you want to delete it?"); 
    String confirmDelete = scan.next(); 

    ynOnly = false; 

    if (confirmDelete.equalsIgnoreCase("Y") 
      && stud.getStudNum().equals(enterStudNum2)) { 
     it.remove(); 
     System.out.print("Delete Successful"); 
     ynOnly = false; 
    } else if (confirmDelete.equalsIgnoreCase("N")) { 
     System.out.print("Deletion did not proceed"); 
     ynOnly = false; 
    } else { 
     System.out.println("\nY or N only\n"); 
     ynOnly = true; 
    } 
} while (ynOnly == true);

}

來源

2016-01-27 16:13:56 pratapvaibhav19

在Arraylist中刪除對象

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