我在玩苹果的新Swift编程语言,遇到了一些问题…

目前我试图读取一个plist文件,在Objective-C中,我会做以下工作来获取内容作为NSDictionary:

NSString *filePath = [[NSBundle mainBundle] pathForResource:@"Config" ofType:@"plist"];
NSDictionary *dict = [[NSDictionary alloc] initWithContentsOfFile:filePath];

我如何得到一个plist作为一个字典在Swift?

我假设我可以得到路径到plist:

let path = NSBundle.mainBundle().pathForResource("Config", ofType: "plist")

当这工作(如果它是正确的?):我如何获得内容作为一个字典?

还有一个更普遍的问题:

是否可以使用默认的NS*类?我想是的……还是我遗漏了什么?据我所知,默认框架NS*类仍然有效,可以使用吗?


当前回答

Swift 4.0 iOS 11.2.6列表解析和代码解析它,基于https://stackoverflow.com/users/3647770/ashok-r上面的答案。

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<array>
  <dict>
    <key>identity</key>
    <string>blah-1</string>
    <key>major</key>
    <string>1</string>
    <key>minor</key>
    <string>1</string>
    <key>uuid</key>
    <string>f45321</string>
    <key>web</key>
    <string>http://web</string>
</dict>
<dict>
    <key>identity</key>
    <string></string>
    <key>major</key>
    <string></string>
    <key>minor</key>
    <string></string>
    <key>uuid</key>
    <string></string>
    <key>web</key>
    <string></string>
  </dict>
</array>
</plist>

do {
   let plistXML = try Data(contentsOf: url)
    var plistData: [[String: AnyObject]] = [[:]]
    var propertyListFormat =  PropertyListSerialization.PropertyListFormat.xml
        do {
            plistData = try PropertyListSerialization.propertyList(from: plistXML, options: .mutableContainersAndLeaves, format: &propertyListFormat) as! [[String:AnyObject]]

        } catch {
            print("Error reading plist: \(error), format: \(propertyListFormat)")
        }
    } catch {
        print("error no upload")
    }

其他回答

如果我想将.plist转换为Swift字典,这是我所做的:

if let path = NSBundle.mainBundle().pathForResource("Config", ofType: "plist") {
  if let dict = NSDictionary(contentsOfFile: path) as? Dictionary<String, AnyObject> {
    // use swift dictionary as normal
  }
}

为Swift 2.0编辑:

if let path = NSBundle.mainBundle().pathForResource("Config", ofType: "plist"), dict = NSDictionary(contentsOfFile: path) as? [String: AnyObject] {
    // use swift dictionary as normal
}

为Swift 3.0编辑:

if let path = Bundle.main.path(forResource: "Config", ofType: "plist"), let dict = NSDictionary(contentsOfFile: path) as? [String: AnyObject] {
        // use swift dictionary as normal
}

Swift 2.0:访问信息。Plist

我有一个名为CoachMarksDictionary的字典,在信息中具有布尔值。Plist。我想访问bool值并使其为真。

let path = NSBundle.mainBundle().pathForResource("Info", ofType: "plist")!
  let dict = NSDictionary(contentsOfFile: path) as! [String: AnyObject]

  if let CoachMarksDict = dict["CoachMarksDictionary"] {
       print("Info.plist : \(CoachMarksDict)")

   var dashC = CoachMarksDict["DashBoardCompleted"] as! Bool
    print("DashBoardCompleted state :\(dashC) ")
  }

写给Plist:

自定义Plist:- Make from File-New-File-Resource-PropertyList。增加了三个字符串:DashBoard_New, DashBoard_Draft, DashBoard_Completed)

func writeToCoachMarksPlist(status:String?,keyName:String?)
 {
  let path1 = NSBundle.mainBundle().pathForResource("CoachMarks", ofType: "plist")
  let coachMarksDICT = NSMutableDictionary(contentsOfFile: path1!)! as NSMutableDictionary
  var coachMarksMine = coachMarksDICT.objectForKey(keyName!)

  coachMarksMine  = status
  coachMarksDICT.setValue(status, forKey: keyName!)
  coachMarksDICT.writeToFile(path1!, atomically: true)
 }

该方法可以调用为

self.writeToCoachMarksPlist(" true - means user has checked the marks",keyName: "the key in the CoachMarks dictionary").

我使用swift字典,但在我的文件管理器类中转换它们和nsdictionary,如下所示:

    func writePlist(fileName:String, myDict:Dictionary<String, AnyObject>){
        let docsDir:String = dirPaths[0] as String
        let docPath = docsDir + "/" + fileName
        let thisDict = myDict as NSDictionary
        if(thisDict.writeToFile(docPath, atomically: true)){
            NSLog("success")
        } else {
            NSLog("failure")
        }

    }
    func getPlist(fileName:String)->Dictionary<String, AnyObject>{
        let docsDir:String = dirPaths[0] as String
        let docPath = docsDir + "/" + fileName
        let thisDict = NSDictionary(contentsOfFile: docPath)
        return thisDict! as! Dictionary<String, AnyObject>
    }

这似乎是最不麻烦的读写方式,但让我的其余代码保持尽可能快。

你仍然可以在Swift中使用nsdictionary:

Swift 4

 var nsDictionary: NSDictionary?
 if let path = Bundle.main.path(forResource: "Config", ofType: "plist") {
    nsDictionary = NSDictionary(contentsOfFile: path)
 }

Swift 3+

if let path = Bundle.main.path(forResource: "Config", ofType: "plist"),
   let myDict = NSDictionary(contentsOfFile: path){
    // Use your myDict here
}

以及旧版本的Swift

var myDict: NSDictionary?
if let path = NSBundle.mainBundle().pathForResource("Config", ofType: "plist") {
    myDict = NSDictionary(contentsOfFile: path)
}
if let dict = myDict {
    // Use your dict here
}

NSClasses仍然可用,完全可以在Swift中使用。我想他们可能很快就会把重点转移到swift上,但是目前swift api并没有核心NSClasses的所有功能。

我已经创建了一个简单的字典初始化器替换NSDictionary(contentsOfFile: path)。只要去掉NS。

extension Dictionary where Key == String, Value == Any {

    public init?(contentsOfFile path: String) {
        let url = URL(fileURLWithPath: path)

        self.init(contentsOfURL: url)
    }

    public init?(contentsOfURL url: URL) {
        guard let data = try? Data(contentsOf: url),
            let dictionary = (try? PropertyListSerialization.propertyList(from: data, options: [], format: nil) as? [String: Any]) ?? nil
            else { return nil }

        self = dictionary
    }

}

你可以这样使用它:

let filePath = Bundle.main.path(forResource: "Preferences", ofType: "plist")!
let preferences = Dictionary(contentsOfFile: filePath)!
UserDefaults.standard.register(defaults: preferences)