无法将文件从包复制到 iOS 中的文档目录

Question

我正在尝试使用以下代码将文件从我的包复制到 iOS 中的文档目录。

let bundlePath = NSBundle.mainBundle().pathForResource("information", ofType: ".png")
print(bundlePath, "\n") //prints the correct path
let destPath = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true).first!
let fileManager = NSFileManager.defaultManager()
let fullDestPath = NSURL(fileURLWithPath: destPath).URLByAppendingPathComponent("information.png")
let fullDestPathString = String(fullDestPath)
print(fileManager.fileExistsAtPath(bundlePath!)) // prints true

do{
try fileManager.copyItemAtPath(bundlePath!, toPath: fullDestPathString)
}catch{
    print("\n")
    print(error)
}

Error Domain=NSCocoaErrorDomain Code=4 "The file “information.png” doesn’t exist." UserInfo={NSSourceFilePathErrorKey=/Users/macbookpro/Library/Developer/CoreSimulator/Devices/E58CA1C6-C6F1-4D72-9572-3925675E78A5/data/Containers/Bundle/Application/EFA83E02-5F24-4BB3-B32A-7E755081A730/AutoLayout tuts.app/information.png, NSUserStringVariant=( Copy ), NSDestinationFilePath=file:///Users/macbookpro/Library/Developer/CoreSimulator/Devices/E58CA1C6-C6F1-4D72-9572-3925675E78A5/data/Containers/Data/Application/86A1BDD5-FAF2-486E-85A9-CF72A547C6CD/Documents/information.png, NSFilePath=/Users/macbookpro/Library/Developer/CoreSimulator/Devices/E58CA1C6-C6F1-4D72-9572-3925675E78A5/data/Containers/Bundle/Application/EFA83E02-5F24-4BB3-B32A-7E755081A730/AutoLayout tuts.app/information.png, NSUnderlyingError=0x7fb53251cd80 {Error Domain=NSPOSIXErrorDomain Code=2 "No such file or directory"}}

根据 fileManager.fileExistsAtPath()，该文件确实存在。我做错了什么？

Answer 1

问题出在这一行：

let fullDestPathString = String(fullDestPath)

应该是：

let fullDestPathString = fullDestPath.path

查看错误。问题是目的地。注意 file:///。您的代码没有正确地将 URL 转换为文件路径。您需要使用 NSURL 的 path 属性来获取字符串形式的路径。

在你所有的调试和检查中，你从未验证过 fullDestPathString 的值。

Answer 2

要获取您应该使用的字符串路径

let path = fullDestPath.path

边注

fileManager.fileExistsAtPath(bundlePath!) == true

是检查值是否为真的方法

fileManager.fileExistsAtPath(bundlePath!)

就是这样会有些问题

Answer 3

请查找代码 Below.i 参考了@rmaddy 的回答。

func CheckDataBaseOnPathorNot() -> Void {
        let bundlePath = Bundle.main.path(forResource: "Project_Expert", ofType: ".db")
        print(bundlePath ?? "", "\n") //prints the correct path
        let destPath = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true).first!
        let fileManager = FileManager.default
        let fullDestPath = NSURL(fileURLWithPath: destPath).appendingPathComponent("Project_Expert.db")
        let fullDestPathString = fullDestPath!.path
        print(fileManager.fileExists(atPath: bundlePath!)) // prints true
        if fileManager.fileExists(atPath: fullDestPathString) {
            print("File is available")
        }else{
            do{
                try fileManager.copyItem(atPath: bundlePath!, toPath: fullDestPathString)
            }catch{
                print("\n")
                print(error)

            }
        }

    }

检查此代码，如果文件在路径上不可用，则复制文件。

谢谢。

Answer 4

Swift 3

func copyfileToDocs()
    {
        let bundlePath = Bundle.main.path(forResource: "db", ofType: ".sqlite")
        print(bundlePath!, "\n") //prints the correct path
        let destPath = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true).first!
        let fileManager = FileManager.default
        let fullDestPath = NSURL(fileURLWithPath: destPath).appendingPathComponent("db.sqlite")
        let fullDestPathString = fullDestPath?.path
        print(fileManager.fileExists(atPath: bundlePath!)) // prints true
        do
        {
            try fileManager.copyItem(atPath: bundlePath!, toPath: fullDestPathString!)
            print("DB Copied")
        }
        catch
        {
            print("\n")
            print(error)
        }
    }

Answer 5

Swift 4

某些答案具有误导性：

print(fileManager.fileExists(atPath: bundlePath!))

因此提出这个 extension 版本：

extension FileManager {
    func copyfileToUserDocumentDirectory(forResource name: String,
                                         ofType ext: String) throws
    {
        if let bundlePath = Bundle.main.path(forResource: name, ofType: ext),
            let destPath = NSSearchPathForDirectoriesInDomains(.documentDirectory,
                                .userDomainMask,
                                true).first {
            let fileName = "\(name).\(ext)"
            let fullDestPath = URL(fileURLWithPath: destPath)
                                   .appendingPathComponent(fileName)
            let fullDestPathString = fullDestPath.path

            if !self.fileExists(atPath: fullDestPathString) {
                try self.copyItem(atPath: bundlePath, toPath: fullDestPathString)
            }
        }
    }
}

用法

try fileManager.copyfileToUserDocumentDirectory(forResource: "information",
                                                ofType: "png")
...

无法将文件从包复制到 iOS 中的文档目录

Can`t copy file from bundle to documents directory in iOS

bundle

copy

ios

swift

Swift 4