Question

在我的Java应用程序中，我有一个很长的JSON字符串，其中包含我想要提取的数据。

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我想要提取的是此格式"56":["81",3,"0","","","","","0","","4754","M",1]下字符串的对象部分（括号内），并从中获取所有这些数据："81",3,"0","","","","","0","","4754","M",1并能够访问其编号。< / p>

要做到这一点，我试过这个：

for(int i = 1; i > 0; i++) {
    String d;
    try {
        d = data.split("\"" + i + "\"\\:\\[")[1];
        d = d.split("\\]")[0];
    } catch(Exception e) {
        e.printStackTrace();
        System.out.println("quit");
        break;
    }
}

问题是我得到一个数组超出范围的异常，以及来自此data.split("\"" + i + "\"\\:\\[")[1]的insta-quit。我的猜测是我把正则表达式搞砸了，但我真的看不到哪里。谢谢你的帮助。

Answer 1

更好地使用JSON Java库。它会真正简化您的解析。下面是一个示例，说明如何提取所需的最后一个数组并将其所有值打印到控制台。

final JSONArray root = new JSONArray(YOUR_JSON_STRING);

final JSONObject numData = root.getJSONObject(1);
final JSONArray numArray = numData.getJSONArray("56");

for (int i = 0; i < numArray.length(); ++i) {
  if (i == 1 || i == 11)
      System.out.print(numArray.getInt(i)+",");
  else
      System.out.print(numArray.getString(i)+",");
}
// prints: "81",3,"0","","","","","0","","4754","M",1,

的参考：
JSON Java API docs

Answer 2

JSON数据应该使用JSON parser提取，绝不能使用正则表达式或任何其他类型的低级字符串处理代码。

Answer 3

看起来你永远不会退出FOR语句，因为它没有上限。

for（int i = 1; i＆gt; 0; i ++）

只要“i＆gt; 0”，FOR语句就会继续，并且你已经从1开始，并且你不断地递增它，所以它永远不会小于或等于零。 / p>

如果您可以使用array.length或其他方法获取数组大小，并将FOR语句更改为：

for（int i = 1; i＆gt; array.length; i ++）

可能会解决问题。

无法按我想要的方式拆分String

3 个答案: