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?
在SWIFT语言中,你可以这样读plist:
let path = NSBundle.mainBundle().pathForResource("PriceList", ofType: "plist")
let dict = NSDictionary(contentsOfFile: path)
读单个字典值:
let test: AnyObject = dict.objectForKey("index1")
如果你想在plist中获得完整的多维字典:
let value: AnyObject = dict.objectForKey("index2").objectForKey("date")
下面是plist:
<plist version="1.0">
<dict>
<key>index2</key>
<dict>
<key>date</key>
<string>20140610</string>
<key>amount</key>
<string>110</string>
</dict>
<key>index1</key>
<dict>
<key>amount</key>
<string>125</string>
<key>date</key>
<string>20140212</string>
</dict>
</dict>
</plist>
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。
以下是我找到的解决方案:
let levelBlocks = NSDictionary(contentsOfFile: NSBundle.mainBundle().pathForResource("LevelBlocks", ofType: "plist"))
let test: AnyObject = levelBlocks.objectForKey("Level1")
println(test) // Prints the value of test
我将测试类型设置为AnyObject,以关闭关于可能发生的意外推断的警告。
而且,它必须在类方法中完成。
访问并保存已知类型的特定值:
let value = levelBlocks.objectForKey("Level1").objectForKey("amount") as Int
println(toString(value)) // Converts value to String and prints it
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").
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
}
通过尼克的回答转换成一个方便的扩展:
extension Dictionary {
static func contentsOf(path: URL) -> Dictionary<String, AnyObject> {
let data = try! Data(contentsOf: path)
let plist = try! PropertyListSerialization.propertyList(from: data, options: .mutableContainers, format: nil)
return plist as! [String: AnyObject]
}
}
用法:
let path = Bundle.main.path(forResource: "plistName", ofType: "plist")!
let url = URL(fileURLWithPath: path)
let dict = Dictionary<String, AnyObject>.contentsOf(path: url)
我敢打赌,它也可以为数组创建类似的扩展