MJExtension (automatic conversion of JSON to data model)
Arranged from: http://www.jianshu.com/p/93c242452b9b.
Reprinted from https://www.cnblogs.com/huoran1120/p/5470480.html
1. Function of MJExtension
Dictionary-->Model
Model-->Dictionary
Dictionary array-->Model array
Model array-->Dictionary array
2.pod import statement pod'MJExtension'
3. Simple data model conversion
Student * stu = [Student mj_objectWithKeyValues:dict];
The attribute name of the object must be consistent with the data in json
If there is a nested model in the model, use this sentence directly, and use. To access
eg：status.retweetedStatus.user.name
4. There are array attributes in the model, and the array contains other models
Implemented inside the model StatusResult
+(NSDictionary *)objectClassInArray{
return @{
@"statuses":@"Status",
@"ads":@"Ad"
}
}
StatusResult * result = [StatusResult mj_objectWithKeyValues:dict];
This way of writing does not need to import Status and Ad header files, the name of the class is written after the colon
for(Status *status in result.statuses) traverse access
5. If the name of the attribute in the model is different from the key of the dictionary (there is also a multi-level mapping)
@interface Student : NSObject
@property (copy, nonatomic) NSString *ID;
@property (copy, nonatomic) NSString *desc;
@property (copy, nonatomic) NSString *nowName;
@property (copy, nonatomic) NSString *oldName;
@property (copy, nonatomic) NSString *nameChangedTime;
@property (strong, nonatomic) Bag *bag;
@end
@interface Bag : NSObject
@property (copy, nonatomic) NSString *name;
@property (assign, nonatomic) double price;
@end
NSDictionary *dict = @{
@"id" : @"20",
@"desciption" : @"孩子",
@"name" : @{
@"newName" : @"lufy",
@"oldName" : @"kitty",
@"info" : @{
@"nameChangedTime" : @"2013-08"
}
},
@"other" : @{
@"bag" : @{
@"name": @"小书包",
@"price" : @100.7
}
}
};
Implement the following method in Student
+(NSDictionary *)mj_replacedKeyFromPropertyName{
return @{
@"ID" : @"id",
@"desc" : @"desciption",
@"oldName" : @"name.oldName",
@"nowName" : @"name.newName",
@"nameChangedTime" : @"name.info.nameChangedTime",
@"bag" : @"other.bag"
};
}
Multi-level mapping, the front is the custom name, and the back is the mapping relationship in the dictionary
6. Convert a dictionary array into a model array
NSArray *dictArray = @[
@{
@"name" : @"Jack",
@"icon" : @"lufy.png",
},
@{
@"name" : @"Rose",
@"icon" : @"nami.png",
}
];
NSArray *userArray = [User mj_objectArrayWithKeyValuesArray:dictArray];
for (User *user in userArray) {
NSLog(@"name=%@, icon=%@", user.name, user.icon);
}
7. Turn a model into a dictionary
NSDictionary *statusDict = status.keyValues;
8. Convert a model array into a dictionary array
NSArray *userArray = @[user1, user2];
NSArray *dictArray = [User keyValuesArrayWithObjectArray:userArray];
NSLog(@"%@", dictArray);