json在我们学习中是不可避免都会遇到的, json使用起来特别方便, 但是对于json的解析会遇到一些问题.

今天的文章直说如何做到解析json数组

一. 解析最简单的Json数组

{"accessToken":"1ed77dd84930e1c99e8feb67fd3b61c",
"tokenType":"bearer",
"refreshToken":"91e4401e8a49d1a88b8b26ee73263b11",
"expiresIn":3600,
"scope":"default"}

这里面很简单的就是字段对应字段的值, 那怎么取出对应的值呢?

private void parseJSONWithJSONObject(String JsonData) {
        try
        {
            JSONArray jsonArray = new JSONArray(JsonData);
            for (int i=0; i < jsonArray.length(); i++)    {
                JSONObject jsonObject = jsonArray.getJSONObject(i);
                String accessToken = jsonObject.getString("accessToken");
                String tokenType = jsonObject.getString("tokenType");
                String refreshToken = jsonObject.getString("refreshToken");
                String expiresIn = jsonObject.getString("expiresIn");
                String scope = jsonObject.getString("scope");
                String jsresult="\n"+"解析结果:"+"\naccessToken: " + accessToken + ";\ntokenType: " + tokenType + ";\nrefreshToken: " + refreshToken+";\nexpiresIn: "+expiresIn+";\nscope: "+scope;
                System.out.println("accessToken" + accessToken + ";tokenType" + tokenType + ";refreshToken" + refreshToken+";expiresIn"+expiresIn+"scope"+scope);
                
            }
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
    }

这样, 我们就把json字符串转换成了字符串数组, 我们想获取json数组里的某个字段的值时就可以像使用数组那样轻而易举.

代码也很简单, 先把Json字符串通过JSONArray类, 进行json序列化. 然后使用JSONObject类直接获取到json数组的内容

二. 嵌套的json解析

这上面相当于一维的json数组解析想必大家理解起来也不难, 但是我们平时还会遇到很多的复杂json数组 (其实并不复杂, 就是多维json数组而已).

* {
 * "deviceId":"35c78968-7449-4dc4-adcd-8154479721b2",
 * "gatewayId":"35c78968-7449-4dc4-adcd-8154479721b2",
 * "nodeType":"GATEWAY",
 * "createTime":"20180803T234419Z",
 * "lastModifiedTime":"20180818T024013Z",
 * "deviceInfo":{"nodeId":"869405030397288","name":"master02","description":null,"manufacturerId":"master01","manufacturerName":"master01","mac":null,"location":"Shenzhen","deviceType":"WaterMeter","model":"master01","swVersion":null,"fwVersion":null,"hwVersion":null,"protocolType":"CoAP","bridgeId":null,"status":"ONLINE","statusDetail":"NONE","mute":"FALSE","supportedSecurity":null,"isSecurity":null,"signalStrength":null,"sigVersion":null,"serialNumber":null,"batteryLevel":null},
 * "services":[
 *              {
 *               "serviceId":"Trash","serviceType":"Trash",
 *               "data":{"Full_warning":17,"Help_msg":0,"Decibels":0,"Worker_msg":0,"Temp":0},
 *               "eventTime":"20180818T024013Z",
 *               "serviceInfo":null
 *               }
 *              ],
 * "connectionInfo":{"protocolType":null},
 * "location":null,
 * "devGroupIds":[]
 * }

 既然说是多维的数组, 那岂不是也是很简单, 数组嵌套数据, 那我们多层解析也不久好了嘛, 所以上面的这个json字符串我的解析方法如下:

 /**
     * 解析Json数组
     * @param JsonData
     */
    private void parseJSONWithJSONObject(String JsonData) {
        try
        {
            String services=null;
            String data=null;
            JSONArray jsonArray = new JSONArray(JsonData);
            for (int i=0; i < jsonArray.length(); i++)    {
                JSONObject jsonObject = jsonArray.getJSONObject(i);
                services = jsonObject.getString("services");
                String eventTime = jsonObject.getString("eventTime");   //时间戳
            }
            JSONArray jsonArray2 = new JSONArray(services);
            for (int i=0; i < jsonArray2.length(); i++)    {
                JSONObject jsonObject = jsonArray2.getJSONObject(i);
                data = jsonObject.getString("data");
            }
            JSONArray jsonArray3 = new JSONArray("["+data+"]");
            for (int i=0; i < jsonArray3.length(); i++)    {
                JSONObject jsonObject = jsonArray3.getJSONObject(i);
                String Full_warning = jsonObject.getString("Full_warning");
                String Help_msg = jsonObject.getString("Help_msg");
                String Decibels = jsonObject.getString("Decibels");
                String Worker_msg = jsonObject.getString("Worker_msg");
                String Temp = jsonObject.getString("Temp");
                Log.d("111",Full_warning+Decibels+Help_msg+Worker_msg+Temp);
            }
            Log.d("111",data);     // {"Full_warning":17,"Help_msg":0,"Decibels":0,"Worker_msg":0,"Temp":0}
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
    }

这样看下来是不是也就是那么回事.

学习中, 有误请指正