Android JSON parsing Kotlin

I wrote it once. Kotlin parsing JSON But, it's really bad, it's just erased, and now it's all sorted out again. By the way, record a little problem that has been going on for a long time today.

1. Let's start with the simplest.

A JSON string: ===== is called jsonstring.

{ "code": "$", "MSG": "Success", "debugmsg": "", "result":{ "Data": "1231414"} }

Well, how to parse it???

You can use a function to

Fun         get_key_string (key:string,jsonstring:string): string {            = ""            try  {               val Jsonobj:jsonobject= jsonobject (jsonstring)                str=jsonobj.getstring (key)              Catch  (e:jsonexception) {                e.printstacktrace ()            }           return  str        } 

How to use it???

Val msg=get_key_string ("msg", "jsonstring")

The first parameter ===== in the JSON string, you want to parse the key, my example above is Code,msg,debugmsg,result, I chose msg

The second parameter, =====, is the name of the JSON string, which is a string, so don't think it's too complicated.

=====success results after MSG parsing

2. Multiple parsing

Is still the example above =====json string name is still called jsonstring

{ "code": "$", "MSG": "Success", "debugmsg": "", "result":{ "Data": "1231414"} }

I want to get data what to do???

Very simple, two-step.

Val result=get_key_string ("Result", "jsonstring")//===== here the second parameter is still jsonstring

Val data=get_key_string ("Data", "result")//===== note that the second parameter here has been turned into result.

3. Parsing int, Boolean type

This is like parsing a string type, just go to the code.

　　

Fun Get_key_boolean (key:string,jsonstring:string): boolean {//Parse to boolean var str:boolean=true            Try{val Jsonobj:jsonobject=jsonobject (jsonstring) str=Jsonobj.getboolean (key)}Catch(e:jsonexception) {e.printstacktrace ()}returnstr} fun Get_key_int (key:string,jsonstring:string): int {//parse to int var str:int=0Try{val Jsonobj:jsonobject=jsonobject (jsonstring) str=Jsonobj.getint (key)}Catch(e:jsonexception) {e.printstacktrace ()}returnSTR}

4. A little bit of resolution ===== parse into list<map<string,any>>===== actually this is more general, a lot of things directly with this can be

For example, a more complicated jsonstring.

　

{  "code": "$",  "MSG": "Success",  "debugmsg": "",  "Result" : {              "data": [         　　　　　　"Key1": "string"
                        "Key2": 123
                        "Key3": True

                      ]
  }
}

Such a jsonstring,key1 corresponds to a string, key2 corresponds to an integral type, Key3 corresponds to a Boolean type

How to parse it???

Fun Getlistmap (key:string, jsonstring:string): List<map<string, any>>{val list= Arraylist<map<string, any>>()            Try{val Jsonobject=Jsonobject (jsonstring) Val Jsonarray=Jsonobject.getjsonarray (Key) for(I in 0..jsonarray.length ()-1) {val JsonObject2=Jsonarray.getjsonobject (i) Val map= Hashmap<string, any>() Val iterator=Jsonobject2.keys () while(Iterator.hasnext ()) {Val Json_key=Iterator.next () var json_value:any? =jsonobject2.get (Json_key)if(Json_value = =NULL) {Json_value= ""} map.put (Json_key, Json_value)} List.add (map)}}Catch(e:jsonexception) {e.printstacktrace ()}returnList}

There are 2 main steps

Val result=get_key_string ("Result", "jsonstring")

Val Data=getlistmap ("Data", "result")

This is 666.

5. Wrap up all the methods you can use

classJsonutil {Companion object {fun get_key_string (key:string,jsonstring:string): string {var str: String= ""Try{val Jsonobj:jsonobject=jsonobject (jsonstring) str=jsonobj.getstring (key)}Catch(e:jsonexception) {e.printstacktrace ()}returnstr} fun Get_key_boolean (key:string,jsonstring:string): boolean {var str:boolean=true            Try{val Jsonobj:jsonobject=jsonobject (jsonstring) str=Jsonobj.getboolean (key)}Catch(e:jsonexception) {e.printstacktrace ()}returnstr} fun Get_key_int (key:string,jsonstring:string): int {var str:int=0Try{val Jsonobj:jsonobject=jsonobject (jsonstring) str=Jsonobj.getint (key)}Catch(e:jsonexception) {e.printstacktrace ()}returnstr} fun getList (key:string, jsonstring:string): List<String>{val list= arraylist<string>()            Try{val Jsonobject=Jsonobject (jsonstring) Val Jsonarray=Jsonobject.getjsonarray (Key) for(I in 0..jsonarray.length ()-1) {val msg=jsonarray.getstring (i) List.add (msg)}} Catch(e:jsonexception) {e.printstacktrace ()}returnlist} fun Getlistmap (key:string, jsonstring:string): List<map<string, any>>{val list= Arraylist<map<string, any>>()            Try{val Jsonobject=Jsonobject (jsonstring) Val Jsonarray=Jsonobject.getjsonarray (Key) for(I in 0..jsonarray.length ()-1) {val JsonObject2=Jsonarray.getjsonobject (i) Val map= Hashmap<string, any>() Val iterator=Jsonobject2.keys () while(Iterator.hasnext ()) {Val Json_key=Iterator.next () var json_value:any? =jsonobject2.get (Json_key)if(Json_value = =NULL) {Json_value= ""} map.put (Json_key, Json_value)} List.add (map)}}Catch(e:jsonexception) {e.printstacktrace ()}returnlist} fun Get_ask_item (key:string,jsonstring:string): ArrayList<myask>?{var myask=arraylist<myask>()            Try{val Jsonobject=Jsonobject (jsonstring) Val Jsonarray=Jsonobject.getjsonarray (Key) for(I in 0..jsonarray.length ()-1) {val Json_ask=Jsonarray.getjsonobject (i) var my_ask=Myask () Val commentcount=json_ask.getstring ("Commentcount") Val Commentid=json_ask.getstring ("Commentid") Val Content=json_ask.getstring ("Content") Val Createtime=json_ask.getstring ("Createtime") Val Gender=json_ask.getstring ("Gender") Val icon=json_ask.getstring ("icon") Val ID=json_ask.getstring ("id") Val Isfavorite=json_ask.getstring ("Isfavorite") Val Iszan=json_ask.getstring ("Iszan") Val Label=json_ask.getstring ("label") Val Link=json_ask.getstring ("link") Val Nickname=json_ask.getstring ("nickname") Val PublisherID=json_ask.getstring ("PublisherID") Val Reward=json_ask.getstring ("Reward") Val Type=json_ask.getstring ("type") Val Zan=json_ask.getstring ("Zan") Val Image_array=json_ask.getjsonarray ("image") var image_list:arraylist<string>?=NULL                     for(J1 in 0..image_array.length ()-1) {val Image_item=image_array.getstring (J1) image_list?. Add (Image_item)} Val thumbnailimage_array=json_ask.getjsonarray ("thumbnailimage") var image_list2:arraylist<string>?=NULL                     for(J2 in 0..thumbnailimage_array.length ()-1) {val Image_item=thumbnailimage_array.getstring (J2) Image_list2?. Add (Image_item)} My_ask.commentid=Commentid My_ask.commentcount=Commentcount my_ask.content=content My_ask.createtime=createtime My_ask.gender=Gender My_ask.icon=icon My_ask.id=ID My_ask.favoriteis=Isfavorite My_ask.zan=Zan My_ask.zanis=Iszan My_ask.label=label My_ask.link=Link My_ask.nickname=Nickname My_ask.publisherid=PublisherID My_ask.reward=Reward My_ask.type=type My_ask.image=image_list my_ask.thumbnailimage=Image_list2 Myask?. Add (my_ask)}returnMyask}Catch(e:jsonexception) {e.printstacktrace ()}returnmyask} }}

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The last one is custom parsing, because the jsonstring in the project can be very complex, so define a class yourself and then parse it in a similar way.

Because my blog name is also called Jason_jan for JSON or a bit of a special, you can say that JSON is really good

　　

Two third-party libraries recommended

Ason=====github Link: Https://github.com/afollestad/ason

Gsonformat=====github Link: Https://github.com/zzz40500/GsonFormat

Android JSON parsing Kotlin