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| 1 | +java中打印一个数组最简单的方法是什么 |
| 2 | +=== |
| 3 | +问题 |
| 4 | +--- |
| 5 | +在java中,数组没有重写toString()方法,所以我如果直接调用数组toStrign()方法的话,我会知道得到它的内存地址。像这样: |
| 6 | +```java |
| 7 | +int[] intArray = new int[] {1, 2, 3, 4, 5}; |
| 8 | +System.out.println(intArray); // 有时候会输出 '[I@3343c8b3' |
| 9 | +``` |
| 10 | +但是实际上我想要的输出效果是 |
| 11 | +```java |
| 12 | +[1, 2, 3, 4, 5] |
| 13 | +``` |
| 14 | +所以打印一个数组最简单的方法是什么?我想要的效果是 |
| 15 | +```java |
| 16 | +// 数字数组: |
| 17 | +int[] intArray = new int[] {1, 2, 3, 4, 5}; |
| 18 | +//输出: [1, 2, 3, 4, 5] |
| 19 | + |
| 20 | +// 对象数组: |
| 21 | +String[] strArray = new String[] {"John", "Mary", "Bob"}; |
| 22 | +//输出: [John, Mary, Bob] |
| 23 | +``` |
| 24 | + |
| 25 | +回答 |
| 26 | +--- |
| 27 | +在JAVA5中使用 Arrays.toString(arr) 或 Arrays.deepToString(arr)来打印数组。 |
| 28 | + |
| 29 | +不要忘了引入import java.util.Arrays; |
| 30 | +```java |
| 31 | +package packageName; |
| 32 | +import java.util.Arrays; |
| 33 | +``` |
| 34 | + |
| 35 | +```java |
| 36 | +int[] intArray = new int[] {1, 2, 3, 4, 5}; |
| 37 | +System.out.println(Arrays.toString(intArray)); |
| 38 | +//输出: [1, 2, 3, 4, 5] |
| 39 | + |
| 40 | +String[] strArray = new String[] {"John", "Mary", "Bob"}; |
| 41 | +System.out.println(Arrays.deepToString(strArray)); |
| 42 | +*//输出: [John, Mary, Bob] |
| 43 | +``` |
| 44 | +Arrays.deepToString与Arrays.toString不同之处在于,Arrays.deepToString更适合打印多维数组<br> |
| 45 | +比如: <br> |
| 46 | + |
| 47 | +```java |
| 48 | +String[][] b = new String[3][4]; |
| 49 | + for (int i = 0; i < 3; i++) |
| 50 | + { |
| 51 | + for (int j = 0; j < 4; j++) |
| 52 | + { |
| 53 | + b[i][j] = "A" + j; |
| 54 | + } |
| 55 | + } |
| 56 | + System.out.println(Arrays.toString(b)); |
| 57 | + //输出[[Ljava.lang.String;@55e6cb2a, [Ljava.lang.String;@23245e75, [Ljava.lang.String;@28b56559] |
| 58 | + System.out.println(Arrays.deepToString(b)); |
| 59 | + //输出[[A0, A1, A2, A3], [A0, A1, A2, A3], [A0, A1, A2, A3]] |
| 60 | + |
| 61 | +``` |
| 62 | +stackoverflow链接: http://stackoverflow.com/questions/409784/whats-the-simplest-way-to-print-a-java-array |
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