@interface ViewController ()<NSURLConnectionDataDelegate>
{
CGFloat totleLength;
NSMutableData *filedata;
BOOL isDownload;
CGFloat reciveTotle;
NSString *filePath;
NSURLConnection *_connection;
}
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
totleLength = [[userDefaults objectForKey:@"totleLength"] floatValue];
reciveTotle = [[userDefaults objectForKey:@"reciveTotle"] floatValue];
if (reciveTotle > 0) {
CGFloat progress = reciveTotle / totleLength;
self.progressView.progress = progress;
self.progressLabel.text = [NSString stringWithFormat:@"%.f%%",progress * 100];
}
}
- (IBAction)btnClick:(UIButton *)sender {
if (isDownload) {
return;
}
NSURL *url = [NSURL URLWithString:@"http://free2.macx.cn:8182/game/BombSquadX401.dmg"];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
if (reciveTotle > 0) {
NSString *value = [NSString stringWithFormat:@"bytes=%d-",(int)reciveTotle];
[request setValue:value forHTTPHeaderField:@"Range"];
}
_connection = [NSURLConnection connectionWithRequest:request delegate:self];
isDownload = true;
NSString *str = url.absoluteString;
NSString *strName = [str lastPathComponent];
filePath = [NSHomeDirectory() stringByAppendingFormat:@"/Documents/%@",strName];
if (![[NSFileManager defaultManager] fileExistsAtPath:filePath]) {
[[NSFileManager defaultManager]createFileAtPath:filePath contents:nil attributes:nil];
}
}
- (IBAction)pauseAction:(UIButton *)sender {
[_connection cancel];
_connection = nil;
[self appendFileData:filedata];
NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
[userDefaults setObject:@(reciveTotle) forKey:@"reciveTotle"];
[userDefaults setObject:@(totleLength) forKey:@"totleLength"];
[userDefaults synchronize];
isDownload = NO;
}
#pragma mark-NSURLConnectionDataDelegate
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSHTTPURLResponse *)response{
filedata = [[NSMutableData alloc]init];
NSDictionary *dic = response.allHeaderFields;
NSNumber *number = [dic objectForKey:@"Content-Length"];
totleLength = [number floatValue];
}
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data{
[filedata appendData:data];
reciveTotle += data.length;
self.progressView.progress = reciveTotle / totleLength;
self.progressLabel.text = [NSString stringWithFormat:@"%.f%%",self.progressView.progress * 100];
if (filedata.length >= 500 * 1000) {
[self appendFileData:filedata];
filedata.data = nil;
}
}
- (void)appendFileData:(NSData *)data
{
if (data.length == 0) {
return;
}
NSFileHandle *fileHandle = [NSFileHandle fileHandleForWritingAtPath:filePath];
[fileHandle seekToEndOfFile];
[fileHandle writeData:data];
[fileHandle closeFile];
}
- (void)connectionDidFinishLoading:(NSURLConnection *)connection{
if(filedata.length < 500 * 1000){
[self appendFileData:filedata];
[filedata setData:nil];
[filedata writeToFile:filePath atomically:YES];
}
self.progressLabel.text = @"下载完成";
isDownload = false;
}
原文地址：http://10594302.blog.51cto.com/10584302/1693313
