iOS 字典转json格式打印

创建nsobject的分类

@implementation NSObject (DDJsonSwitch)
-(void)fb_descriptionJson:(NSDictionary *)dicM callBack:(void(^)(NSString * logMessage))callBack
{
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
NSString *logString;
@try {
logString=[[NSString alloc] initWithData:[NSJSONSerialization dataWithJSONObject:dicM options:NSJSONWritingPrettyPrinted error:nil] encoding:NSUTF8StringEncoding];
callBack ? callBack(logString) : nil;
} @catch (NSException *exception) {
NSString *reason = [NSString stringWithFormat:@"reason:%@",exception.reason];
logString = [NSString stringWithFormat:@"转换失败:\n%@,\n转换终止,输出如下:\n%@",reason,self.description];
} @finally {

    }
});

}
@end

调用方法：
[self fb_descriptionJson:dict callBack:^(NSString * _Nullable logMessage) {
NSLog(@"object22222 ==== %@",object);
}];