####获取图片 的方法代码
```
-(void)avatarTap:(id)sender{
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"设置头像" message:@"" preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction *cancelAction = [UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:^(UIAlertAction *action) {
NSLog(@"The \"Okay/Cancel\" alert's cancel action occured.");
}];
UIAlertAction* fromPhotosAlbumAction = [UIAlertAction actionWithTitle:@"从相册选择" style:UIAlertActionStyleDefault handler:^(UIAlertAction * action) { UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
imagePicker.sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;
imagePicker.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
imagePicker.allowsEditing = YES;
imagePicker.delegate = self;
[self presentViewController:imagePicker animated:YES completion:nil];
}];
UIAlertAction* fromPhotoAction = [UIAlertAction actionWithTitle:@"从图库选择" style:UIAlertActionStyleDefault handler:^(UIAlertAction * action) { UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
imagePicker.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
imagePicker.allowsEditing = YES;
imagePicker.delegate = self;
[self presentViewController:imagePicker animated:YES completion:nil];
}];
UIAlertAction* fromCameraAction = [UIAlertAction actionWithTitle:@"相机拍摄" style:UIAlertActionStyleDefault handler:^(UIAlertAction * action) {
if([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera])
{
UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
imagePicker.delegate = self;
imagePicker.allowsEditing = YES;
imagePicker.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
imagePicker.sourceType = UIImagePickerControllerSourceTypeCamera;
[self presentViewController:imagePicker animated:YES completion:nil];
}
}];
[alertController addAction:cancelAction];
[alertController addAction:fromCameraAction];
[alertController addAction:fromPhotoAction];
[alertController addAction:fromPhotosAlbumAction];
[self presentViewController:alertController animated:YES completion:nil];
}
```
###如何进行 压缩
```
UIImage *smallImage=[self scaleFromImage:image toSize:CGSizeMake(240.0f, 240.0f)];//将图片尺寸改为240x240
[UIImageJPEGRepresentation(smallImage, 1.0f) writeToFile:imageFilePath atomically:YES];//写入jpg文件
+ (UIImage *)imageWithCGImage:(CGImageRef)cgImage scale:(CGFloat)scale orientation:(UIImageOrientation)orientation NS_AVAILABLE_IOS(4_0);
```
该方面使用一个CGImageRef创建UIImage，在创建时还可以指定方法倍数以及旋转方向。当scale设置为1的时候，新创建的图像将和原图像尺寸一摸一样，而orientaion则可以指定新的图像的绘制方向。
也可以用这个方法进行压缩 你会发现 得到的 大小 会小了很多倍 如果想测试的话可以 装换成 nsdata 打印一下 哦了。
```
+ (UIImage *) scaleFromImage: (UIImage *) image toSize: (CGSize) size
{
UIGraphicsBeginImageContext(size);
[image drawInRect:CGRectMake(0, 0, size.width, size.height)];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}
```
接着我们就贴代码了 上传 加压缩
```
+ (void)requestToUploadImage:(UIImage*)image completion:(void(^)(NSString * upfile,int code,NSError*error))complete{
NSString * url = URL_UPTOIMAGE;
AFHTTPSessionManager * manager = [AFHTTPSessionManager manager]; //请求和接受的格式
manager.responseSerializer = [AFJSONResponseSerializer serializer]; manager.requestSerializer = [AFJSONRequestSerializer serializer]; manager.responseSerializer.acceptableContentTypes = [NSSet setWithObjects:@"application/json",@"text/json",@"text/html",@"text/javascript",@"text/html", nil];
//请求超时
[manager.requestSerializer willChangeValueForKey:@"timeoutInterval"]; manager.requestSerializer.timeoutInterval = 10.0;
[manager.requestSerializer didChangeValueForKey:@"timeoutInterval"]; [manager POST:url parameters:nil constructingBodyWithBlock:^(idformData) {
//NSData * fileData1 = UIImageJPEGRepresentation(image, 0.1);
//ZLLog(@"%lu",(unsigned long)fileData1.length);
BOOL success;
NSFileManager *fileManager = [NSFileManager defaultManager];
NSError *error;
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *imageFilePath = [documentsDirectory stringByAppendingPathComponent:@"selfPhoto.jpg"];
NSLog(@"imageFile->>%@",imageFilePath);
success = [fileManager fileExistsAtPath:imageFilePath];
if(success) {
success = [fileManager removeItemAtPath:imageFilePath error:&error];
}
UIImage *smallImage=[self scaleFromImage:image toSize:CGSizeMake(240.0f, 240.0f)];
[UIImageJPEGRepresentation(smallImage, 1.0f) writeToFile:imageFilePath atomically:YES];
UIImage *selfPhoto = [UIImage imageWithContentsOfFile:imageFilePath];
NSData * fileData = UIImageJPEGRepresentation(selfPhoto, 0.1);
//ZLLog(@"%lu",(unsigned long)fileData.length);
//使用日期生成图片名称
NSDateFormatter * formatter = [[NSDateFormatter alloc]init];
formatter.dateFormat = @"yyyy-MM-dd HH:mm:ss";
NSString * fileName = [NSString stringWithFormat:@"%@.png",[formatter stringFromDate:[NSDate date]]];
[formData appendPartWithFileData:fileData name:@"upfile" fileName:fileName mimeType:@"jpg"];
} success:^(NSURLSessionDataTask *task, id responseObject) {
NSDictionary * dic = responseObject;
//ZLLog(@"%@",responseObject);
NSString * address = dic[@"data"];
int code = [dic[@"code"] intValue];
if (complete) {
complete(address,code,nil);
}
} failure:^(NSURLSessionDataTask *task, NSError *error) {
if (complete) {
complete(nil,0,error);
}
}];
}
```
