NSURLConnection上传，进度条

结合上一篇下载NSURLConnection下载大小文件，断点下载

本片介绍上传，显示进度条

- (IBAction)showImgPicker:(UIButton *)sender{    //UIImagePickerController  图片选择器    UIImagePickerController *imgPicker = [[UIImagePickerController alloc]init ];        //allowsEditing  是否允许编辑    imgPicker.allowsEditing = YES;    //isSourceTypeAvailable  设置图片来源，默认为相册，可以设置为摄像头    if (![UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera])    {        NSLog(@"摄像头不可用");    }    else    {        imgPicker.sourceType = UIImagePickerControllerSourceTypeCamera;    }    imgPicker.delegate = self;    [self presentViewController:imgPicker animated:YES completion:nil];    [imgPicker release];}/** * 选择完成图片时调用 */- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)image editingInfo:(NSDictionary *)editingInfo{    _imgView.image = image;    [self dismissViewControllerAnimated:YES completion:nil];}//上传图片- (IBAction)UploadImageClick:(UIButton *)sender{    NSURL *url = [NSURL URLWithString:@"http://127.0.0.1:8080/FileUploadServer/UploadServlet"];        NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];    //上传文件必须用POST请求    [request setHTTPMethod:@"POST"];    //forHTTPHeaderField 设置请求头   Content-type,请求体中的数据格式    [request addValue:@"multipart/form-data" forHTTPHeaderField:@"Content-type"];        //UIImageJPEGRepresentation  把一个UIImage转成jpg格式的数据，第二个参数是压缩比例，范围0～1    //NSData *data = UIImageJPEGRepresentation(_imgView.image, 0.7);    //UIImagePNGRepresentation   把一个UIImage转成png格式的数据    NSData *data = UIImagePNGRepresentation(_imgView.image);    //把图片数据放入请求体    [request setHTTPBody:data];        NSURLConnection *connection = [NSURLConnection connectionWithRequest:request delegate:self];    [connection start];}//上传大文件- (IBAction)uploadFile:(UIButton *)sender{    NSString *path = [[NSBundle mainBundle]pathForResource:@"file" ofType:@"zip"];    //NSInputStream  输入流 ，用于大量数据的输入    //inputStreamWithFileAtPath  创建一个文件的输入流    NSInputStream *stream = [NSInputStream inputStreamWithFileAtPath:path];        NSURL *url = [NSURL URLWithString:@"http://127.0.0.1:8080/FileUploadServer/UploadServlet"];    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];    //上传文件必须用POST请求    [request setHTTPMethod:@"POST"];    //设置请求头   Content-type,请求体中的数据格式    [request addValue:@"multipart/form-data" forHTTPHeaderField:@"Content-type"];        //获得上传文件大小    NSDictionary *attDic = [[NSFileManager defaultManager]attributesOfItemAtPath:path error:nil];    [request addValue:[NSString stringWithFormat:@"%lld",[attDic fileSize]] forHTTPHeaderField:@"Content-Length"];    //setHTTPBodyStream  设置请求体的输入流,当上传的数据量很大时，无法全部读入内粗，就需要用输入就上传    [request setHTTPBodyStream:stream];        NSURLConnection *connection = [NSURLConnection connectionWithRequest:request delegate:self];    [connection start];}- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error{    NSLog(@"请求失败:%@",error);}- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response{}- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data{}- (void)connectionDidFinishLoading:(NSURLConnection *)connection{    NSLog(@"上传完毕！");}//当发送出数据时调用- (void)connection:(NSURLConnection *)connection didSendBodyData:(NSInteger)bytesWritten totalBytesWritten:(NSInteger)totalBytesWritten totalBytesExpectedToWrite:(NSInteger)totalBytesExpectedToWrite{    //NSLog(@"%ld----%ld----%ld",bytesWritten,totalBytesWritten,totalBytesExpectedToWrite);    _progressView.progress = (double)totalBytesWritten / (double)totalBytesExpectedToWrite;}