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| #import "ViewController.h"
@interface ViewController ()<NSURLConnectionDataDelegate>
@property(nonatomic,strong) NSFileHandle *writeHandle;
@property(nonatomic,assign) long long totalLength;
@property(nonatomic,assign) long long currentLength;
@end
@implementation ViewController
-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
{
[self download];
}
-(void)download
{
//1-URL
NSURL *url=[NSURL URLWithString:@"http://localhost:8080//MJServer/resources/videos.zip"];
//2-请求
NSURLRequest *request=[NSURLRequest requestWithURL:url];
//3-下载
[NSURLConnection connectionWithRequest:request delegate:self];
}
//-请求失败时调用(请求超时，网络异常)
-(void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error
{
NSLog(@"didFailWithError--");
}
//-接收到服务器的响应聚会调用
-(void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
NSLog(@"didReceiveResponse--");
//文件路径
NSString *caches=[NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES)lastObject];
NSString *filePath=[caches stringByAppendingPathComponent:@"videos.zip"];
//创建一个空的文件到沙盒中
NSFileManager *mgr=[NSFileManager defaultManager];
[mgr createFileAtPath:filePath contents:nil attributes:nil];
//创建一个用来写数据的句柄
self.writeHandle=[NSFileHandle fileHandleForWritingAtPath:filePath];
//获得文件的总大小
self.totalLength=response.expectedContentLength;
}
//当接收到服务器返回到实体数据时调用(具体内容，这个内容可被调用多次)
-(void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
//移动到文件的最后面
[self.writeHandle seekToEndOfFile];
//写入数据到沙盒中
[self.writeHandle writeData:data];
self.currentLength+=data.length;
NSLog(@"下载进度：%f",(double)self.currentLength/self.totalLength);
}
//加载完毕后调用(服务器的数据已经完全返回后)
-(void)connectionDidFinishLoading:(NSURLConnection *)connection
{
NSLog(@"connectionDidFinishLoading--");
self.currentLength=0;
self.totalLength=0;
//关闭文件
[self.writeHandle closeFile];
self.writeHandle=nil;
}
@end
|
