后台返回null iOS

1。第一种解决方案

就是在每一个 可能传回null 的地方 使用  if([object isEqual：[NSNUll null]]) 去判断

2。第二种解决方案

网上传说老外写了一个Category，叫做NullSafe..只支持到ios9,3  ,实测 并没有解决我的问题..

3。第三种解决方案

p.p1 { margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #3495af }
p.p2 { margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #b4261a }
p.p3 { margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #000000 }
span.s1 { }
span.s2 { color: #000000 }
span.s3 { color: #0433ff }
span.s4 { color: #3495af }

AFHTTPSessionManager *manager = [AFHTTPSessionManager manager];

AFJSONResponseSerializer *serializer = [AFJSONResponseSerializer serializer];

serializer.removesKeysWithNullValues = YES;

[serializer setAcceptableContentTypes:[NSSet setWithObjects:@"application/json", @"text/html",@"text/json",@"text/javascript",@"text/plain", nil]];

manager.responseSerializer=serializer;

manager.requestSerializer = [AFJSONRequestSerializer serializer];

不知道为什么无效，有大神给指导一下吗

4。第四种解决方案

json转model时，每个model里加上

p.p1 { margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #000000 }
p.p2 { margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #0433ff }
p.p3 { margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #000000; min-height: 13.0px }
span.s1 { }
span.s2 { color: #0433ff }
span.s3 { color: #3495af }
span.s4 { color: #000000 }

- (id)valueForUndefinedKey:(NSString *)key

{

return nil;

}

- (void)setValue:(id)value forUndefinedKey:(NSString *)key

{

}

5。第5种解决方案

在数组和字典的category里面写的两个方法. 完美解决..在每次请求回来数据,统一处理..

废话不多说,上代码

字典的类目：

p.p1 { margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #b4261a }
p.p2 { margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #000000 }
p.p3 { margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #000000; min-height: 13.0px }
p.p4 { margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #3495af }
p.p5 { margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #0433ff }
span.s1 { color: #0433ff }
span.s2 { }
span.s3 { color: #3495af }
span.s4 { color: #000000 }

#import "NSDictionary+Extension.h"

#import "NSArray+Extension.h"

@implementation NSDictionary (Extension)

- (NSDictionary *)dictionaryByReplacingNulls {

const NSMutableDictionary *replaced = [self mutableCopy];

const id nul = [NSNull null];

for (NSString *key in self) {

id object = [self objectForKey:key];

if (object == nul) [replaced removeObjectForKey:key];

else if ([object isKindOfClass:[NSDictionary class]]) [replaced setObject:[object dictionaryByReplacingNulls] forKey:key];

else if ([object isKindOfClass:[NSArray class]]) [replaced setObject:[object arrayByReplacingNulls] forKey:key];

}

return [NSDictionary dictionaryWithDictionary:[replaced copy]];

}

@end

数组的类目：

p.p1 { margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #b4261a }
p.p2 { margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #000000 }
p.p3 { margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #000000; min-height: 13.0px }
p.p4 { margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #3495af }
p.p5 { margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #0433ff }
span.s1 { color: #0433ff }
span.s2 { }
span.s3 { color: #3495af }
span.s4 { color: #000000 }

#import "NSArray+Extension.h"

#import "NSDictionary+Extension.h"

@implementation NSArray (Extension)

- (NSArray *)arrayByReplacingNulls  {

NSMutableArray *replaced = [self mutableCopy];

const id nul = [NSNull null];

for (int idx = 0; idx < [replaced count]; idx++) {

id object = [replaced objectAtIndex:idx];

if (object == nul) [replaced removeObjectAtIndex:idx];

else if ([object isKindOfClass:[NSDictionary class]]) [replaced replaceObjectAtIndex:idx withObject:[object dictionaryByReplacingNulls]];

else if ([object isKindOfClass:[NSArray class]]) [replaced replaceObjectAtIndex:idx withObject:[object arrayByReplacingNulls]];

}

return [replaced copy];

}

@end

在封装的网络请求获取到后台数据的地方 将数据处理一下

p.p1 { margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #3495af }
p.p2 { margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #000000 }
span.s1 { }
span.s2 { color: #000000 }

NSDictionary *dict = [responseObject dictionaryByReplacingNulls];

success(dict);

6。第6种解决方案

大力推荐：

AvoidCrash再也不怕程序崩溃啦 AvoidCrash的功能不仅仅是数组,还有报错字典等许多功能,具体用法可以参考https://github.com/chenfanfang/AvoidCrash

我的项目目前调用了3456这4种解决方案。请各位大神帮我分析利弊。