此答案仅适用于物理设备！

This answer relevant on physical device ONLY!

访问摄像头：

- (void)takePhoto {

    UIImagePickerController *picker = [[UIImagePickerController alloc] init];
    picker.delegate = self;
    picker.allowsEditing = YES;
    picker.sourceType = UIImagePickerControllerSourceTypeCamera;

    [self presentViewController:picker animated:YES completion:NULL];

}

访问相机胶卷：

- (void)selectPhoto {

    UIImagePickerController *picker = [[UIImagePickerController alloc] init];
    picker.delegate = self;
    picker.allowsEditing = YES;
    picker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;

    [self presentViewController:picker animated:YES completion:NULL];


}

实现UIImagePickerController的委托方法：

Implementing the Delegate Methods of UIImagePickerController:

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {

    UIImage *chosenImage = info[UIImagePickerControllerEditedImage];
    self.imageView.image = chosenImage;

    [picker dismissViewControllerAnimated:YES completion:NULL];

}

这个：

- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker {

    [picker dismissViewControllerAnimated:YES completion:NULL];

}

源代码这里