iOS 利用 ASI 实现的异步队列下载文件

概述: 首先 导入ASI网络请求框架 ASI 需要导入的系统库 : CFNetwork.framework
SystemConfiguration.framework MobileCoreServices.framework CoreGraphics.framework libz.dylib
本功能主要使用到 ASIHTTPRequest
和 ASINetworkQueue

.h 文件

#import <Foundation/Foundation.h>

#import "ASIHTTPRequest.h"

#import "ASINetworkQueue.h"
@interface DownLoadManage :
NSObject

@property (nonatomic)double fileSiz;
//文件全部大小

@property (nonatomic)long
long DidDownLoadLenth;
//已经下载的文件大小
@property (nonatomic,strong)ASINetworkQueue
*netWorkQueue;
//下载队列

+ (DownLoadManage *)DefaultManage;
-(void)createQuue;
- (void)startDownLoadFileByFile:(SongsList *)songlist;

.m 文件

#import "DownLoadManage.h"

#define RequestOutTime 120
//设置超时时间
@implementation DownLoadManage
static
DownLoadManage *downLoadManage =
nil;
+ (id)DefaultManage{

static dispatch_once_t onceToken;

dispatch_once(&onceToken, ^{

downLoadManage = [[DownLoadManage
alloc]
init];
});

return
downLoadManage;
}
//创建异步队列
- (void)createQuue {

if (self.netWorkQueue ==
nil) {

ASINetworkQueue *que = [[ASINetworkQueue
alloc]
init];

self.netWorkQueue = que;

[self.netWorkQueue
reset];

[self.netWorkQueue
setShowAccurateProgress:YES];

[self.netWorkQueue
setShouldCancelAllRequestsOnFailure:NO];

[self.netWorkQueue
setMaxConcurrentOperationCount:1];
[self.netWorkQueue
go];

//
创建存放路径

//初始化Documents路径

NSString *path = [NSHomeDirectory()
stringByAppendingPathComponent:@"Documents"];

//初始化临时文件路径

NSString *folderPath = [path
stringByAppendingPathComponent:@"/DownLoad/temp"];

//创建文件管理器

NSFileManager *fileManager = [NSFileManager
defaultManager];

//判断temp文件夹是否存在

BOOL fileExists = [fileManager
fileExistsAtPath:folderPath];

if (!fileExists) {//如果不存在说创建,因为下载时,不会自动创建文件夹
[fileManager
createDirectoryAtPath:folderPath

withIntermediateDirectories:YES

attributes:nil

error:nil];
}
}

}
//创建请求并将请求加入队列
- (void)startDownLoadFileByFile:(NSString *)fileName {

//初始化保存路径

NSString *savePath = [FileSavePath
stringByAppendingPathComponent:[NSString
stringWithFormat:@"DownLoad/%@.mp3",fileName]];

//初始下载连接

NSString *strUrl = [NSString
stringWithFormat:@"http://bcs.duapp.com/preschoolteaching/song/%@.mp3",songlist.songName];

NSString *URL = [strUrl
stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

NSURL *url = [NSURL
URLWithString:URL];

//设置下载连接

ASIHTTPRequest *request = [[ASIHTTPRequest
alloc]
initWithURL:url];

//设置ASIHTTPRequest代理
request.delegate =
self;

//初始化保存ZIP文件路径
NSString *savePath = [path stringByAppendingPathComponent:[NSString stringWithFormat:@"book_%d.zip",[sender
tag]]];

//初始化临时文件路径

NSString *tmpDir =
NSTemporaryDirectory();

NSString *tempPath = [tmpDir
stringByAppendingPathComponent:[NSString
stringWithFormat:@"%@.mp3.temp",songlist.songName]];

//设置文件保存路径

[request
setDownloadDestinationPath:savePath];

//设置临时文件路径

[request
setTemporaryFileDownloadPath:tempPath];

//设置进度条的代理,

[request
setDownloadProgressDelegate:self];

//设置是是否支持断点下载
[request setAllowResumeForFileDownloads:YES];

//设置超时时间

[request setTimeOutSeconds:RequestOutTime];

//设置基本信息 用来标记请求
[request
setUserInfo:[NSDictionary
dictionaryWithObjectsAndKeys:songlist.songTag,@"bookID",songlist.songName,@"fileName",nil]];

//添加到ASINetworkQueue队列去下载
[self.netWorkQueue
addOperation:request];

}

#pragma mark ASIHTTPRequestDelegate method

//ASIHTTPRequestDelegate,下载之前获取信息的方法,主要获取下载内容的大小，可以显示下载进度多少字节
- (void)request:(ASIHTTPRequest *)request didReceiveResponseHeaders:(NSDictionary
*)responseHeaders {
//获取 请求对象的标记

int bookid = [[request.userInfo objectForKey:@"bookID"] intValue];

//文件开始下载

}

//下载中
- (void)request:(ASIHTTPRequest *)request didReceiveBytes:(long
long)bytes {

//获取 请求对象的标记
int bookid = [[request.userInfo
objectForKey:@"bookID"]
intValue];

//下载中
}

//ASIHTTPRequestDelegate,下载完成时,执行的方法
- (void)requestFinished:(ASIHTTPRequest *)request {

int bookid = [[request.userInfo
objectForKey:@"bookID"]
intValue];

//下载完成设置文件
防止备份到iCloud和iTunes上

NSString *fileName = [request.userInfo
objectForKey:@"fileName"];

NSString *savePath = [FileSavePath
stringByAppendingPathComponent:[NSString
stringWithFormat:@"DownLoad/%@.mp3",fileName]];

NSURL *url = [NSURL
fileURLWithPath:savePath];

[self
addSkipBackupAttributeToItemAtURL:url];

if ([self.delegate
respondsToSelector:@selector(DownLoadManageaSIdidFinishDownLoadByid:)]) {

[self.delegate
DownLoadManageaSIdidFinishDownLoadByid:bookid];
}
}
- (void)requestFailed:(ASIHTTPRequest *)request {

//获取 请求对象的标记

int bookid = [[request.userInfo
objectForKey:@"bookID"]
intValue];

//文件下载失败
}

//下载完成设置文件
防止备份到iCloud和iTunes上
- (BOOL)addSkipBackupAttributeToItemAtURL:(NSURL *)URL
{

assert([[NSFileManager
defaultManager] fileExistsAtPath: [URL
path]]);

NSError *error = nil;

BOOL success = [URL
setResourceValue: [NSNumber
numberWithBool: YES]

forKey: NSURLIsExcludedFromBackupKey
error: &error];

if(!success){

VSLog(@"Error excluding %@ from backup %@", [URL
lastPathComponent], error);
}else {

VSLog(@"防止备份属性设成功");
}

return success;
}