暫存

• Documents: 存放应用程序产生的数据，会被itunes备份同步
• Library: 包含两个子目录：Caches 和 Preferences
  • Preferences：包含应用程序的偏好设置文件。您不应该直接创建偏好设置文件，而是应该使用NSUserDefaults类来取得和设置应用程序的偏好,会被itunes备份同步.
  • Caches：用于存放应用程序专用的支持文件，保存应用程序再次启动过程中需要的信息,不会被itunes备份同步。
• tmp: 存放临时数据,当不在用时应该删除掉临时文件,系统也有可能在程序不运行时删除该文件夹下内容

##获取目录方法

###Home目录

//获取沙盒主目录路径 
var homeDir=NSHomeDirectory()
println("\(dirHome)")

###Documents目录

 //获取Documents目录路径
  var paths = NSSearchPathForDirectoriesInDomains(NSSearchPathDirectory.DocumentDirectory, NSSearchPathDomainMask.UserDomainMask, true)
    var documentsDirectory = paths[0] as! String
    println("\(documentsDirectory)")

或者相对Home路径

var documentsDirectory = NSHomeDirectory().stringByAppendingPathComponent("Documents")

    println("\(documentsDirectory)")

###Library目录

    // 获取Library目录路径  
     var paths = NSSearchPathForDirectoriesInDomains(NSSearchPathDirectory.LibraryDirectory, NSSearchPathDomainMask.UserDomainMask, true)
        var libraryDirectory = paths[0] as! String
        println("\(libraryDirectory)")

或者相对Home路径

    var libraryDirectory = NSHomeDirectory().stringByAppendingPathComponent("Library")

    println("\(libraryDirectory)")

###Cache目录

// 获取Caches目录路径  
 var paths = NSSearchPathForDirectoriesInDomains(NSSearchPathDirectory.CachesDirectory, NSSearchPathDomainMask.UserDomainMask, true)
        var cacheDirectory = paths[0] as! String
        println("\(cacheDirectory)")

###tmp目录

    // 获取tmp目录路径
  var tmpDirectory = NSTemporaryDirectory()

    println("\(tmpDirectory)")

或者相对Home目录

    var tmpDirectory = NSHomeDirectory().stringByAppendingPathComponent("tmp")

    println("\(tmpDirectory)");

##文件操作

###创建文件夹

    //在Documents目录下创建test文件夹
    var documentDir = NSHomeDirectory().stringByAppendingPathComponent("Documents")
       var fileManager  = NSFileManager.defaultManager()
       var testDir = documentDir.stringByAppendingPathComponent("test")

       var error:NSError?=nil

       var result = fileManager.createDirectoryAtPath(testDir, withIntermediateDirectories: true, attributes: nil, error: &error)

        if result {
            println("success")
        }else {
            println("error:\(error)")
        }

###创建文件

  //在Documents目录下test文件夹下创建test.txt
  var documentDir = NSHomeDirectory().stringByAppendingPathComponent("Documents")
   var fileManager  = NSFileManager.defaultManager()
   var testDir = documentDir.stringByAppendingPathComponent("test")

   var fileDir = testDir.stringByAppendingPathComponent("test.txt")

   var error:NSError?=nil

   var result = fileManager.createFileAtPath(fileDir, contents: nil, attributes: nil)

    if result {
        println("success")
    }else {
        println("error:\(error)")
    }

###写入文件

   var documentDir = NSHomeDirectory().stringByAppendingPathComponent("Documents")
   var fileManager  = NSFileManager.defaultManager()
   var testDir = documentDir.stringByAppendingPathComponent("test")

   var fileDir = testDir.stringByAppendingPathComponent("test.txt")

   var error:NSError?=nil
   var content = "this is a test"

   var result = content.writeToFile(fileDir, atomically: true, encoding: NSUTF8StringEncoding, error: &error)

    if result {
        println("success")
    }else {
        println("error:\(error)")
    }

###读取文件

  var documentDir = NSHomeDirectory().stringByAppendingPathComponent("Documents")
       var fileManager  = NSFileManager.defaultManager()
       var testDir = documentDir.stringByAppendingPathComponent("test")

       var fileDir = testDir.stringByAppendingPathComponent("test.txt")

       var error:NSError?=nil

       var content = NSString(contentsOfFile: fileDir, encoding: NSUTF8StringEncoding, error: &error)

        if error == nil  {
            println("success content:\(content!)")
        }else {
            println("error:\(error)")
        }

###读取文件属性

var documentDir = NSHomeDirectory().stringByAppendingPathComponent("Documents")
       var fileManager  = NSFileManager.defaultManager()
       var testDir = documentDir.stringByAppendingPathComponent("test")

       var fileDir = testDir.stringByAppendingPathComponent("test.txt")

       var error:NSError?=nil

       var attrs = fileManager.attributesOfFileSystemForPath(fileDir, error: &error)

        if error == nil  {
            println("success content:\(attrs)")
        }else {
            println("error:\(error)")
        }

###删除文件

 var documentDir = NSHomeDirectory().stringByAppendingPathComponent("Documents")
       var fileManager  = NSFileManager.defaultManager()
       var testDir = documentDir.stringByAppendingPathComponent("test")

       var fileDir = testDir.stringByAppendingPathComponent("test.txt")

       var error:NSError?=nil

       var attrs = fileManager.removeItemAtPath(fileDir, error: &error)

        if error == nil  {
            println("success")
        }else {
            println("error:\(error)")
        }

###判断是否为目录

var documentDir = NSHomeDirectory().stringByAppendingPathComponent("Documents")
       var fileManager  = NSFileManager.defaultManager()
       var testDir = documentDir.stringByAppendingPathComponent("test")

       var isDir = ObjCBool(false)
       var existsDir = fileManager.fileExistsAtPath(testDir, isDirectory:&isDir)

        if existsDir {
            println("exists Dir")
        }else {
            println("not exists")
        }