Question

怎样获取json格式的数组长度

Answer 1

import org.json.JSONArray;
import org.json.JSONException;

public class test2 {
public static void main(String[] args) throws JSONException {
String str = "[{'columnId':5,'columnName':'人文历史'},{'columnId':2,'columnName':'商业视野'}]}";
JSONArray jsonArray = null;
jsonArray = new JSONArray(str);
System.out.println(jsonArray.getJSONObject(0).get("columnName"));
}

}
需要引入json.jar