iOS系统异步请求封装

在iOS开发中，我们经常会遇到网络请求的问题，AFNetworking是一个很不错的第三方库。当然iOS系统也有自己的网络异步请求类——NSURLConnection，虽然每次用的时候都要写代理，但是封装一下之后还是很好用的。封装的这个类除了完成异步网络请求，还加入了MD5的加密以及本地缓存。

// HttpDownLoadBlock.h

#import <Foundation/Foundation.h>

@interface HttpDownLoadBlock : NSObject<NSURLConnectionDataDelegate,NSURLConnectionDelegate>

@property(nonatomic,strong)NSURLConnection * myConnection;

@property(nonatomic,strong)NSMutableData * data;

//文件生成路径

@property(nonatomic,copy)NSString * path;

//结果

@property(nonatomic,strong)NSArray * dataArray;

@property(nonatomic,strong)NSDictionary * dataDic;

@property(nonatomic,strong)UIImage * dataImage;

//需要block指针

@property(nonatomic,copy)void(^httpDownLoad)(BOOL , HttpDownLoadBlock *);

//外部调用的方法

-(id)initWithStrUrl:(NSString *)strUrl Block:(void(^)(BOOL,HttpDownLoadBlock *))a;

@end

// HttpDownLoadBlock.m

#import "HttpDownLoadBlock.h"

#import "MyMD5.h"

#import "NSFileManager+Method.h"

@implementation HttpDownLoadBlock

-(id)initWithStrUrl:(NSString*)strUrl Block:(void(^)(BOOL,HttpDownLoadBlock*))a{

if (self=[super init]) {

//保存匿名函数指针

self.httpDownLoad=a;

NSLog(@"%@",a);

if (strUrl==nil) {

return
self;

}

self.path=[NSString stringWithFormat:@"%@/Documents/%@",NSHomeDirectory(),[MyMD5 md5:strUrl]];

NSFileManager*manager=[NSFileManager defaultManager];

if ([manager fileExistsAtPath:self.path]&&![manager timeOutWithPath:[MyMD5 md5:strUrl] timeOut:60*60]) {

//有缓存时

self.data=[NSData dataWithContentsOfFile:self.path];

[self jsonValue];

}else{

//发起网络请求

[self requestDownLoad:strUrl];

}

}

return
self;

}

//开始请求

-(void)requestDownLoad:(NSString*)strUrl{

[UIApplication sharedApplication].networkActivityIndicatorVisible=YES;

self.myConnection=[NSURLConnection connectionWithRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:strUrl]] delegate:self];

}

-(void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response

{

//接收到数据，开始接收数据

self.data=[NSMutableData dataWithCapacity:0];

}

-(void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data

{

//持续接收数据

[self.data appendData:data];

}

-(void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error

{

//请求失败

[UIApplication sharedApplication].networkActivityIndicatorVisible=NO;

UIAlertView*alertView=[[UIAlertView alloc]initWithTitle:@"提示" message:@"您的网络有问题，请检查网络"
delegate:self cancelButtonTitle:nil otherButtonTitles:@"确定",
nil];

[alertView show];

if (self.httpDownLoad) {

self.httpDownLoad(NO,self);

}

}

-(void)connectionDidFinishLoading:(NSURLConnection *)connection

{

[UIApplication sharedApplication].networkActivityIndicatorVisible=NO;

//保存数据

[self.data writeToFile:self.path atomically:YES];

[self jsonValue];

}

-(void)jsonValue{

id result=[NSJSONSerialization JSONObjectWithData:self.data options:NSJSONReadingMutableContainers error:nil];

if ([result isKindOfClass:[NSArray class]]) {

self.dataArray=result;

}else{

if ([result isKindOfClass:[NSDictionary class]]) {

self.dataDic=result;

}else{

if (self.data) {

self.dataImage=[UIImage imageWithData:self.data];

}

}

}

if (self.httpDownLoad) {

NSLog(@"%@",self.httpDownLoad);

self.httpDownLoad(YES,self);

}

}

@end