ios23- 文件下载（同步和异步）

1.第一步：创建一个单例视图

#import <uikit/uikit.h>

 

@interface ios23_downviewcontroller : uiviewcontroller<nsurlconnectiondelegate,nsurlconnectiondatadelegate>{

    nsmutabledata *connectiondata;

   
}

-(ibaction)tongbu;

-(ibaction)yibu;

@property (nonatomic,retain) nsmutabledata *connectiondata;

@end

2
//

//  ios23_downviewcontroller.m

//  ios23-down

//

//  created by  on 13-6-17.

//  copyright 2013年 __mycompanyname__. all rights reserved.

//

 

#import "ios23_downviewcontroller.h"

 

@implementation ios23_downviewcontroller

@synthesize connectiondata;

 

- (void)didreceivememorywarning

{

    [super didreceivememorywarning];

    // release any cached data, images, etc that aren't in use.

}

 

#pragma mark - view lifecycle

-(ibaction)tongbu{

    nslog(@"同步");

    nserror *err;

    //定义url

    nsstring ";

    //构建nsurl

    nsurl *fileurl=[nsurl urlwithstring:url];

    //构建nsurlrequest

    nsurlrequest *request=[[nsurlrequest alloc]initwithurl:fileurl];

    //建立连接

    nsdata *data=[nsurlconnection sendsynchronousrequest:request returningresponse:nil error:&err];

    if (data.length>0) {

        nsstring *savepath=[[nshomedirectory()stringbyappendingpathcomponent:@"documents"]stringbyappendingpathcomponent:@"test.zip"];

        //当数据写入的时候

        if ([data writetofile:savepath atomically:yes]) {

            nslog(@"保存成功");

        }else{

            nslog(@"保存失败");

        }

    }

               
          
}

-(ibaction)yibu{

    nslog(@"异步");

    nserror *err;

    //定义url

    nsstring ";

    //构建nsurl

    nsurl *fileurl=[nsurl urlwithstring:url];

    //构建nsurlrequest

    nsurlrequest *request=[[nsurlrequest alloc]initwithurl:fileurl];

    //建立连接

    nsdata *data=[nsurlconnection sendsynchronousrequest:request returningresponse:nil error:&err];

    nsurlconnection *conn=[[nsurlconnection alloc]initwithrequest:request delegate:self];

    //初始化connectiondata;

    connectiondata=[[nsmutabledata alloc]init ];

   
}

//接受数据

-(void)connection:(nsurlconnection *)connection didreceivedata:(nsdata *)data{

    //获取服务器传递的数据

    [connectiondata appenddata:data];

}

//接收数据成功

-(void)connectiondidfinishloading:(nsurlconnection *)connection{

    if (connectiondata.length>0) {

        nsstring *savepath=[[nshomedirectory()stringbyappendingpathcomponent:@"documents"]stringbyappendingpathcomponent:@"test.zip"];

        //当数据写入的时候

        if ([connectiondata writetofile:savepath atomically:yes]) {

            nslog(@"保存成功");

        }else{

            nslog(@"保存失败");

        }

    }}

//接收数据失败

-(void)connection:(nsurlconnection *)connection didfailwitherror:(nserror *)error{}

- (void)viewdidload

{

    [super viewdidload];

// do any additional setup after loading the view, typically from a nib.

}

 

- (void)viewdidunload

{

    [super viewdidunload];

    // release any retained subviews of the main view.

    // e.g. self.myoutlet = nil;

}

 

- (void)viewwillappear:(bool)animated

{

    [super viewwillappear:animated];

}

 

- (void)viewdidappear:(bool)animated

{

    [super viewdidappear:animated];

}

 

- (void)viewwilldisappear:(bool)animated

{

[super viewwilldisappear:animated];

}

 

- (void)viewdiddisappear:(bool)animated

{

[super viewdiddisappear:animated];

}

 

- (bool)shouldautorotatetointerfaceorientation:(uiinterfaceorientation)interfaceorientation

{

    // return yes for supported orientations

    return (interfaceorientation != uiinterfaceorientationportraitupsidedown);

}

 

@end