我在跟踪a tutorial titled "Swift Tutorial for iOS : NSFileManager Persisting Data",在29分钟前后遇到了一个错误.当我try 在iOS模拟器上运行它时,我收到错误:
由于未捕获的异常"NSUnknownKeyException"而终止应用程序,原因:"[setValue:forUndefinedKey:]:此类不符合key-theLoadMethod的键值编码."
显然,基于这个错误,我认为问题在于我的theLoadMethod
.以下是我在ViewController中作为该项目的一部分编写的代码:
let theDocumentsFolder = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)[0] as String
let theFileName = "/theUserFile.txt"
let thePath = theDocumentsFolder.stringByAppendingString(theFileName)
class ViewController: UIViewController {
@IBOutlet weak var nameTextField: UITextField!
@IBOutlet weak var lastNameTextField: UITextField!
@IBOutlet weak var ageTextField: UITextField!
@IBOutlet weak var theLabel: UILabel!
// The save method
@IBAction func theSaveMethod(sender: AnyObject) {
var name = nameTextField.text
var lastName = lastNameTextField.text
var age = ageTextField.text
var theString = "The user's information is: \(name), \(lastName), \(age)"
let theFileManager = NSFileManager.defaultManager()
if !theFileManager.fileExistsAtPath(thePath) {
var writeError:NSError?
let fileToBeWritten = theString.writeToFile(thePath, atomically: true, encoding: NSUTF8StringEncoding, error: &writeError)
if writeError == nil {
println("No errors. Added: \(theString)")
} else {
println("Encountered an error. Error is: \(writeError)")
}
} else {
println("File already exists")
}
nameTextField.resignFirstResponder()
lastNameTextField.resignFirstResponder()
ageTextField.resignFirstResponder()
}
@IBAction func theLoadMethod(sender: AnyObject) {
let infoFromFile:String = String.stringWithContentsOfFile(thePath, encoding: NSUTF8StringEncoding, error: nil)!
theLabel.text = infoFromFile
}
我做错什么了吗?据我所知,我所有的iOS屏幕元素都被正确命名和链接.