ios 在 Swift 3.0 中创建目录

Create Directory in Swift 3.0

提问by Neeld

I am a new student in 9th grade learning swift, creating a school project .

我是 9 年级的新生，学习swift，正在创建一个学校项目。

I am trying to create a directory where I want to save a scanned file into pdf format.

我正在尝试创建一个目录，我想在其中将扫描的文件保存为 pdf 格式。

While creating directory I am getting error below.

在创建目录时，我收到以下错误。

Error 1:

错误 1：

Cannot use instance member 'filemgr' within property initializer; property initializers run before 'self' is available.

不能在属性初始值设定项中使用实例成员“filemgr”；属性初始值设定项在 'self' 可用之前运行。

Error 2:

错误 2：

Expected declaration

预期申报

Code:

代码：

let filemgr = FileManager.default


let dirPaths = filemgr.urls(for: .documentDirectory, in: .userDomainMask)

let docsURL = dirPaths[0]

let newDir = docsURL.appendingPathComponent("data").path

do{
    try filemgr.createDirectory(atPath: newDir,withIntermediateDirectories: true, attributes: nil)
} catch {
    print("Error: \(error.localizedDescription)")
}

Please assist me in resolving this issue.

请帮助我解决这个问题。

Thanks.

谢谢。

回答by Avinash

For Swift 4.0Please use this

对于Swift 4.0请使用这个

    let fileManager = FileManager.default
    if let tDocumentDirectory = fileManager.urls(for: .documentDirectory, in: .userDomainMask).first {
        let filePath =  tDocumentDirectory.appendingPathComponent("\(FOLDER_NAME)") 
        if !fileManager.fileExists(atPath: filePath.path) {
            do {
                try fileManager.createDirectory(atPath: filePath.path, withIntermediateDirectories: true, attributes: nil)
            } catch {
                NSLog("Couldn't create document directory")
            }
        }
        NSLog("Document directory is \(filePath)")
    }

回答by Pragnesh Vitthani

Pls, use this code:

请使用此代码：

Swift 4.0And Swift 3.0

Swift 4.0和 Swift 3.0

let DocumentDirectory = NSURL(fileURLWithPath: NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0])
let DirPath = DocumentDirectory.appendingPathComponent("FOLDER_NAME")
do
{
    try FileManager.default.createDirectory(atPath: DirPath!.path, withIntermediateDirectories: true, attributes: nil)
}
catch let error as NSError
{
    print("Unable to create directory \(error.debugDescription)")
}
print("Dir Path = \(DirPath!)")

回答by CodeBender

For Swift 4.0, I created the following extension off of URLthat allows for the creation of a folder off of the documents directory within the application.

对于Swift 4.0，我创建了以下扩展URL，允许在应用程序中的文档目录之外创建文件夹。

import Foundation

extension URL {
    static func createFolder(folderName: String) -> URL? {
        let fileManager = FileManager.default
        // Get document directory for device, this should succeed
        if let documentDirectory = fileManager.urls(for: .documentDirectory,
                                                    in: .userDomainMask).first {
            // Construct a URL with desired folder name
            let folderURL = documentDirectory.appendingPathComponent(folderName)
            // If folder URL does not exist, create it
            if !fileManager.fileExists(atPath: folderURL.path) {
                do {
                    // Attempt to create folder
                    try fileManager.createDirectory(atPath: folderURL.path,
                                                    withIntermediateDirectories: true,
                                                    attributes: nil)
                } catch {
                    // Creation failed. Print error & return nil
                    print(error.localizedDescription)
                    return nil
                }
            }
            // Folder either exists, or was created. Return URL
            return folderURL
        }
        // Will only be called if document directory not found
        return nil
    }
}

If the desired folder does not exist, it will create it. Then, assuming the folder exists, it returns the URLback to the user. Otherwise, if it fails, then nilis returned.

如果所需的文件夹不存在，它将创建它。然后，假设文件夹存在，它将返回URL给用户。否则，如果失败，则nil返回。

For example, to create the folder "MyStuff", you would call it like this:

例如，要创建文件夹“MyStuff”，您可以这样称呼它：

let myStuffURL = URL.createFolder(folderName: "MyStuff")

This would return:

这将返回：

file:///var/mobile/Containers/Data/Application/4DE0A1C0-8629-47C9-87D7-C2B4F3A16D24/Documents/MyStuff/

file:///var/mobile/Containers/Data/Application/4DE0A1C0-8629-47C9-87D7-C2B4F3A16D24/Documents/MyStuff/

You can also create nested folders with the following:

您还可以使用以下内容创建嵌套文件夹：

let myStuffHereURL = URL.createFolder(folderName: "My/Stuff/Here")

Which gives you:

这给了你：

file:///var/mobile/Containers/Data/Application/4DE0A1C0-8629-47C9-87D7-C2B4F3A16D24/Documents/My/Stuff/Here/

file:///var/mobile/Containers/Data/Application/4DE0A1C0-8629-47C9-87D7-C2B4F3A16D24/Documents/My/Stuff/Here/

回答by pkc456

You are getting this because you are assigning value to newDirinstance at wrong place.

你得到这个是因为你newDir在错误的地方为实例赋值。

I wrote your code in viewDidLoadand it works perfectly.

我写了你的代码viewDidLoad，它工作得很好。