NSURLConnection上传，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;
}