通过UIImagepickerController在swift中获取元数据

我试图在SWIFT中的Objective-C的iOS 8 UIImage元数据中实现如下的答案

//source: http://stackanswers.com/questions/24227578/ios-8-uiimage-metadata func metaDataFromAssetLibrary(info: NSDictionary) { var assetURL = info.objectForKey(UIImagePickerControllerReferenceURL) as NSURL var assetLibrary = ALAssetsLibrary() assetLibrary.assetForURL(assetURL as NSURL, resultBlock: { (asset: ALAsset!) in var metadata: NSDictionary = asset.defaultRepresentation().metadata() as NSDictionary NSLog ("imageMetaData from AssetLibrary %@",metadata); }, failureBlock: { (error: NSError!) in NSLog("Error!") }) } 

我打电话给它

 func imagePickerController(picker: UIImagePickerController!, didFinishPickingMediaWithInfo info: NSDictionary!){ // https://stackoverflow.com/questions/3088874/didfinishpickingmediawithinfo-return-nil-photo picker.dismissViewControllerAnimated(true, completion: nil) let image = info.objectForKey("UIImagePickerControllerOriginalImage") as UIImage PHPhotoLibrary.sharedPhotoLibrary().performChanges({ let createAssetRequest = PHAssetChangeRequest.creationRequestForAssetFromImage(image) let assetPlaceholder = createAssetRequest.placeholderForCreatedAsset let albumChangeRequest = PHAssetCollectionChangeRequest(forAssetCollection: self.assetCollection, assets: self.photosAsset) albumChangeRequest.addAssets([assetPlaceholder]) }, completionHandler: {(success, error)in NSLog("Adding Image to Library -> %@", (success ? "Sucess":"Error!")) picker.dismissViewControllerAnimated(true, completion: nil) }) metaDataFromAssetLibrary(info) } 

导致一个“致命的错误：意外地发现零，而展开一个可选值”

Answer 1

试试这个代码：

 let metadata = info[UIImagePickerControllerMediaMetadata] as? NSDictionary let image = info[UIImagePickerControllerOriginalImage] as? UIImage 

Answer 2

如果你从相机获取图像，你可以从信息[UIImagePickerControllerMediaMetadata]获取元数据。

但是，当你从相册中select图像，没有信息[UIImagePickerControllerMediaMetadata]，但信息[UIImagePickerControllerReferenceURL]！