Question

我有以下内容：

   String[][] content = {
            {"c","d", "2"},
            {"e","f", "3"},
            {"g","h", "4"},
            {"i","j", "5"}} ;

如何在现有元素中添加一些1x3元素？

Answer 1

    public static void main(String[] args) {
        String[][] content = {
                {"c","d", "2"},
                {"e","f", "3"},
                {"g","h", "4"},
                {"i","j", "5"}};

        String[][] newContent = {{"p","a", "3"}};

        System.out.println(Arrays.deepToString(append(content, newContent)));
    }

    public static String[][] append(String[][] a, String[][] b) {
        String[][] result = new String[a.length + b.length][];
        System.arraycopy(a, 0, result, 0, a.length);
        System.arraycopy(b, 0, result, a.length, b.length);
        return result;
    }

<强>输出

[[c, d, 2], [e, f, 3], [g, h, 4], [i, j, 5], [p, a, 3]]

另一项输入

String[][] content = {
                {"c","d", "2"},
                {"S","2"},
                {"i","j", "5"},{"p","1"}};

String[][] newContent = {{"p","a", "3"},{"k","3"}};

<强>输出

[[c, d, 2], [S, 2], [i, j, 5], [p, 1], [p, a, 3], [k, 3]]

Answer 2

这很麻烦，涉及创建整个数组的副本，因此无法定期执行：

String[][] content = {
        {"c","d", "2"},
        {"e","f", "3"},
        {"g","h", "4"},
        {"i","j", "5"}};
content = Arrays.copyOf(content, content.length + 1);
content[content.length - 1] = new String[] { "k", "l", "6" };

但是你可以使用List：

List<String[]> list = new ArrayList<>();
Collections.addAll(list, content);
list.add(new String[] { "k", "l", "6" });

通过以下操作：

String[] row = list.remove(2);
list.get(1)[3]; // Getting
list.add(0, row); // Adding at an index

如何将元素追加到String [] []？

2 个答案: