這里要說的重點不是在與JsonModel 本身有的方法的常規寫法,而是如何全局忽略無關屬性.(每個Model 都寫一下下面的方法,豈不是很蛋(_^))

方式一.可選屬性 (就是說這個屬性可以為null或者為空)

{
  "id": "123",
  "name": null,
  "price": 12.95
}
@interface ProductModel : JSONModel
@property (assign, nonatomic) int id;
@property (strong, nonatomic) NSString<Optional>* name;
@property (assign, nonatomic) float price;
@property (strong, nonatomic) NSNumber<Optional>* uuid;
@end

@implementation ProductModel
@end

方式二.忽略屬性 (就是完全忽略這個屬性)

{
  "id": "123",
  "name": null
}
@interface ProductModel : JSONModel
@property (assign, nonatomic) int id;
@property (strong, nonatomic) NSString<Ignore>* customProperty;
@end

@implementation ProductModel
@end

方式三.設置所有的屬性為可選(所有屬性值可以為空)

@implementation ProductModel
+(BOOL)propertyIsOptional:(NSString*)propertyName
{
  return YES;
}
@end

重點在這里 propertyIsOptional方法默認返回的是NO;攔截該方法,使其返回YES.(當然,如果你修改JsonModel 源碼,當我沒說)

#import "objc/runtime.h"
@implementation  JSONModel (SafeJSONModel)

+(void)load{
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        SEL org_Selector = @selector(propertyIsOptional:);
        SEL dt_Selector  = @selector(dt_propertyIsOptional:);
        
        Method org_method = class_getClassMethod([self class], org_Selector);
        Method dt_method  = class_getClassMethod([self class], dt_Selector);
        
        class_addMethod(self, org_Selector, method_getImplementation(dt_method), method_getTypeEncoding(dt_method));
//        if (isAdd) {
//            class_replaceMethod(self, dt_Selector, method_getImplementation(org_method), method_getTypeEncoding(org_method));
//        }else{
            method_exchangeImplementations(org_method, dt_method);
//        }
        
    });
}
+(BOOL)dt_propertyIsOptional:(NSString *)propertyName{
    [self dt_propertyIsOptional:propertyName];
    return YES;
}

@end