Android中对json的解析和处理
大树 2011-02-14
在android调用webservice时,经常要对json的格式进行处理,现在有两种方法
去处理:
1使用JSONObject和JSONTokener去解析
2使用GSON库
先看第一种方法,假如有如下的json字符串:
{
“name”:“myName”,
“message”:["myMessage1","myMessage2"],
“place”:“myPlace”,
“date”:”thisDate”
}
第一种解决方法:
publicclassmainextendsActivity{
@Override
publicvoidonCreate(BundlesavedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
try{
TextViewtv=(TextView)findViewById(R.id.TextView01);
Stringjson=“{”
+“\”name\”:\”myName\”,”
+“\”message\”:[\"myMessage1\",\"myMessage2\"],”
+“\”place\”:\”myPlace\”,”
+“\”date\”:\”thisDate\””
+“}”;
/*CreateaJSONobjectandparsetherequiredvalues*/
JSONObjectobject=(JSONObject)newJSONTokener(json).nextValue();
Stringname=object.getString(“name”);
Stringplace=object.getString(“place”);
Stringdate=object.getString(“date”);
JSONArraymessage=object.getJSONArray(“message”);
tv.setText(“Name:“+name+”\n\n”);
tv.append(“Place:“+place+”\n\n”);
tv.append(“Date:“+date+”\n\n”);
for(inti=0;i<message.length();i++)
{
tv.append(“Message:“+message.getString(i)+”\n\n”);
}
2使用GSON类库
GOOGLE提供的gson类库,地址在:
代码如下:
publicclassJSON_structure{
publicStringname;
publicStringplace;
publicStringdate;
publicString[]message;
}
这其实是个POJO类
try{
/*InflateTextViewfromthelayout*/
TextViewtv=(TextView)findViewById(R.id.TextView01);
/*JSONdataconsideredasanexample.Generallythisdataisobtained
fromawebservice.*/
Stringjson=“{”
+“\”name\”:\”myName\”,”
+“\”message\”:[\"myMessage1\",\"myMessage2\"],”
+“\”place\”:\”myPlace\”,”
+“\”date\”:\”thisDate\””
+“}”;
Gsongson=newGson();
JSON_structureobj=gson.fromJson(json,JSON_structure.class);
tv.setText(“Name:“+obj.name+”\n\n”);
tv.append(“Place:“+obj.place+”\n\n”);
tv.append(“Date:“+obj.date+”\n\n”);
for(inti=0;i<obj.message.length;i++)
{
tv.append(“Message:“+obj.message[i]+”\n\n”);
}
}
catch(Exceptionex){ex.printStackTrace();}
}
}catch(JSONExceptione){e.printStackTrace();}
catch(Exceptionex){ex.printStackTrace();}
}
}
