android – 错误org.json.JSONException：PROJECT_NAME没有值这是我的json

我收到错误org.json.JSONException：PROJECT_NAME没有值这是我的json

{"PROJECTS":[ 
         {
            "PROJECT_NUMBER": "2062",
            "PROJECT_NAME": "OPW 51183"
         },
         {
            "PROJECT_NUMBER": "404",
            "PROJECT_NAME": "404"
         },
         {
            "PROJECT_NUMBER": "2125",
            "PROJECT_NAME": "OPW 50016"
         },
         {
            "PROJECT_NUMBER": ""
         },
         {
            "PROJECT_NUMBER": "2130",
            "PROJECT_NAME": "OPW 51151 63rd & Shirley SEW S"
         },
         {
            "PROJECT_NUMBER": "2159",
            "PROJECT_NAME": "OPW 51226"
         }
        ]

    }

和鳕鱼是：

for (int i = 0; i < innerProjectarray.length(); i++) 
    {

JSONObject obj=innerProjectarray.getJSONObject(i);
String projectnumber1=obj.getString("PROJECT_NUMBER");
String projectname1=obj.getString("PROJECT_NAME");
        }

有没有办法找到密钥,如果密钥不存在,那么np需要获取值od特定字符串帮助我谢谢

解决方法:

使用has检查Json中是否存在密钥.如果此对象具有name的映射,则返回true.

喜欢

for (int i = 0; i < innerProjectarray.length(); i++) {

    JSONObject obj = innerProjectarray.getJSONObject(i);
    if (obj.has("PROJECT_NUMBER")) {
        String projectnumber1 = obj.getString("PROJECT_NUMBER");
    }

    if (obj.has("PROJECT_NAME")) {
        String projectname1 = obj.getString("PROJECT_NAME");
    }
}

另一种方法是使用optString,如果存在,则返回按名称映射的值,必要时强制它.如果不存在此类映射,则返回空字符串.

for (int i = 0; i < innerProjectarray.length(); i++) {

    JSONObject obj = innerProjectarray.getJSONObject(i);

    String projNum = obj.optString("PROJECT_NUMBER"); 
    String projName = obj.optString("PROJECT_NAME"); 
    // and use both values. 
}