使用FileManager复制文件时出错(CFURLCopyResourcePropertyForKey失败,因为它传递了一个没有方案的URL)

Question

我正在尝试使用FileManager's 将一些(媒体)文件从一个文件夹复制到另一个文件夹copyItem(at:path:),但我收到错误:

CFURLCopyResourcePropertyForKey失败,因为它传递了一个没有方案的URL错误Domain = NSCocoaErrorDomain Code = 262"由于不支持指定的URL类型,因此无法打开该文件."

我正在使用Xcode 9 beta和Swift 4.

let fileManager = FileManager.default
let allowedMediaFiles = ["mp4", "avi"]

func isMediaFile(_ file: URL) -> Bool {
    return allowedMediaFiles.contains(file.pathExtension)
}

func getMediaFiles(from folder: URL) -> [URL] {
    guard let enumerator = fileManager.enumerator(at: folder, includingPropertiesForKeys: []) else { return [] }

    return enumerator.allObjects
        .flatMap {$0 as? URL}
        .filter { $0.lastPathComponent.first != "." && isMediaFile($0)   
    }
}

func move(files: [URL], to location: URL) {
    do {
        for fileURL in files {
            try fileManager.copyItem(at: fileURL, to: location)
        }
    } catch (let error) {
        print(error)
    }
}


let mediaFilesURL = URL(string: "/Users/xxx/Desktop/Media/")!
let moveToFolder = URL(string: "/Users/xxx/Desktop/NewFolder/")!

let mediaFiles = getMediaFiles(from: mediaFilesURL)

move(files: mediaFiles, to: moveToFolder)

Answer 1

发生错误是因为

URL(string: "/Users/xxx/Desktop/Media/")!

创建没有方案的URL.您可以使用

URL(string: "file:///Users/xxx/Desktop/Media/")!

或者更简单地说,

URL(fileURLWithPath: "/Users/xxx/Desktop/Media/")

另请注意,fileManager.copyItem()目标中必须包含文件名,而不仅仅是目标目录:

try fileManager.copyItem(at: fileURL,
                    to: location.appendingPathComponent(fileURL.lastPathComponent))