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  • Swift

    ios开发经常会遇到读文件，写文件等，对文件和文件夹的操作，这时就可以使用NSFileManager，NSFileHandle等类来实现。

    下面总结了各种常用的操作：

    1，遍历一个目录下的所有文件
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    //假设用户文档下有如下文件和文件夹[test1.txt,fold1/test2.txt]
    let manager = NSFileManager.defaultManager()
    let urlForDocument = manager.URLsForDirectory( NSSearchPathDirectory.DocumentDirectory, inDomains:NSSearchPathDomainMask.UserDomainMask)
    let url = urlForDocument[0] as NSURL
    var error:NSErrorPointer = nil
     
    //（1）对指定路径执行浅搜索，返回指定目录路径下的文件、子目录及符号链接的列表
    let contentsOfPath = manager.contentsOfDirectoryAtPath(url.path!, error: error)
    //contentsOfPath：Optional([fold1, test1.txt])
    println("contentsOfPath: (contentsOfPath)") 
     
    //（2）类似上面的，对指定路径执行浅搜索，返回指定目录路径下的文件、子目录及符号链接的列表
    let contentsOfURL = manager.contentsOfDirectoryAtURL(url, includingPropertiesForKeys: nil, options: NSDirectoryEnumerationOptions.SkipsHiddenFiles, error: error);
    //contentsOfURL：Optional([file://Users/.../Application/.../Documents/fold1/,
    // file://Users/.../Application/.../Documents/test1.txt])
    println("contentsOfURL: (contentsOfURL)")
     
    //（3）深度遍历，会递归遍历子文件夹（但不会递归符号链接）
    let enumeratorAtPath = manager.enumeratorAtPath(url.path!)
    //enumeratorAtPath：Optional([fold1, fold1/test2.txt, test1.txt])
    println("enumeratorAtPath: (enumeratorAtPath?.allObjects)") 
     
    //（4）类似上面的，深度遍历，会递归遍历子文件夹（但不会递归符号链接）
    let enumeratorAtURL = manager.enumeratorAtURL(url, includingPropertiesForKeys: nil, options: NSDirectoryEnumerationOptions.SkipsHiddenFiles, errorHandler:nil)
    //contentsOfURL：Optional([file://Users/.../Application/.../Documents/fold1/,
    // file://Users/.../Application/.../Documents/fold1/test2.txt,
    // file://Users/.../Application/.../Documents/test1.txt])
    println("enumeratorAtURL: (enumeratorAtURL?.allObjects)")
     
    //（5）深度遍历，会递归遍历子文件夹（包括符号链接，所以要求性能的话用enumeratorAtPath）
    let subPaths = manager.subpathsAtPath(url.path!)
    //subPaths：Optional([fold1, fold1/test2.txt, test1.txt])
    println("subPaths: (subPaths)")

    2，判断文件或文件夹是否存在

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    let fileManager = NSFileManager.defaultManager()
    let filePath:String = NSHomeDirectory() + "/Documents/hangge.txt"
    var exist = fileManager.fileExistsAtPath(filePath)


    3，创建文件夹 

    方式1：
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    let myDirectory:String = NSHomeDirectory() + "/Documents/myFolder/Files"
    let fileManager = NSFileManager.defaultManager()
    var error:NSErrorPointer = nil
    //withIntermediateDirectories为ture表示路径中间如果有不存在的文件夹都会创建
    var isSuccess:Bool = fileManager.createDirectoryAtPath(myDirectory,
        withIntermediateDirectories: true, attributes: nil, error: error)
    方式2：
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    func createFolder(name:String,baseUrl:NSURL){
        let manager = NSFileManager.defaultManager()
        var error:NSErrorPointer = nil
        let folder = baseUrl.URLByAppendingPathComponent(name, isDirectory: true)
        println("文件夹: (folder)")
        let exist = manager.fileExistsAtPath(folder.path!)
        if !exist {
            let createSuccess = manager.createDirectoryAtURL(folder, withIntermediateDirectories: true, attributes: nil, error: error)
            println("文件夹创建结果: (createSuccess)")
        }
    }
     
    //在文档目录下新建folder目录
    let manager = NSFileManager.defaultManager()
    let urlForDocument = manager.URLsForDirectory( NSSearchPathDirectory.DocumentDirectory, inDomains:NSSearchPathDomainMask.UserDomainMask)
    let url = urlForDocument[0] as NSURL
    var error:NSErrorPointer = nil
    createFolder("folder", baseUrl: url)

    4，将对象写入文件
    可以通过writeToFile方法，可以创建文件并将对象写入，对象包括String，NSString，UIImage，NSArray，NSDictionary等。
    （1）把String保存到文件
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    let filePath:String = NSHomeDirectory() + "/Documents/hangge.txt"
    var error:NSErrorPointer = nil
    var info = "欢迎来到hange.com"
    info.writeToFile(filePath, atomically: true, encoding: NSUTF8StringEncoding, error: error)

    （2）把图片保存到文件路径下
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    let filePath:String = NSHomeDirectory() + "/Documents/hangge.png"
    var image = UIImage(named: "apple.png")
    var data:NSData = UIImagePNGRepresentation(image)
    data.writeToFile(filePath, atomically: true)

    （3）把NSArray保存到文件路径下
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    var array = NSArray(objects: "aaa","bbb","ccc")
    let filePath:String = NSHomeDirectory() + "/Documents/array.plist"
    array.writeToFile(filePath, atomically: true)

    （4）把NSDictionary保存到文件路径下
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    var dictionary = NSDictionary(objects: ["111","222"], forKeys: ["aaa","bbb"])
    let filePath:String = NSHomeDirectory() + "/Documents/dictionary.plist"
    dictionary.writeToFile(filePath, atomically: true)

    5，创建文件
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    func createFile(name:String,fileBaseUrl:NSURL){
        let manager = NSFileManager.defaultManager()
        var error:NSErrorPointer = nil
         
        let file = fileBaseUrl.URLByAppendingPathComponent(name)
        println("文件: (file)")
        let exist = manager.fileExistsAtPath(file.path!)
        if !exist {
            let data = NSData(base64EncodedString:"aGVsbG8gd29ybGQ=",options:.IgnoreUnknownCharacters)
            let createSuccess = manager.createFileAtPath(file.path!,contents:data,attributes:nil)
            println("文件创建结果: (createSuccess)")
        }
    }
     
    //在文档目录下新建test.txt文件
    let manager = NSFileManager.defaultManager()
    let urlForDocument = manager.URLsForDirectory( NSSearchPathDirectory.DocumentDirectory, inDomains:NSSearchPathDomainMask.UserDomainMask)
    let url = urlForDocument[0] as NSURL
    var error:NSErrorPointer = nil
    createFile("test.txt", fileBaseUrl: url)
    //createFile("folder/new.txt", fileBaseUrl: url)

    6，复制文件 

    （1）方法1

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    let fileManager = NSFileManager.defaultManager()
    let homeDirectory = NSHomeDirectory()
    var error:NSErrorPointer = nil
    let srcUrl = homeDirectory + "/Documents/hangge.txt"
    let toUrl = homeDirectory + "/Documents/copyed.txt"
    fileManager.copyItemAtPath(srcUrl, toPath: toUrl, error: error)


    （2）方法2

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    // 定位到用户文档目录
    let manager = NSFileManager.defaultManager()
    let urlForDocument = manager.URLsForDirectory( NSSearchPathDirectory.DocumentDirectory, inDomains:NSSearchPathDomainMask.UserDomainMask)
    let url = urlForDocument[0] as NSURL
    var error:NSErrorPointer = nil
     
    let contentsOfURL = manager.contentsOfDirectoryAtURL(url, includingPropertiesForKeys: nil, options: NSDirectoryEnumerationOptions.SkipsHiddenFiles, error: error);
    // 将test.txt文件拷贝到文档目录根目录下的copyed.txt文件
    let srcUrl = url.URLByAppendingPathComponent("test.txt")
    let toUrl = url.URLByAppendingPathComponent("copyed.txt")
     
    let copyItemSuccess = manager.copyItemAtURL(srcUrl, toURL: toUrl, error: error)
    println("复制结果: (copyItemSuccess)")

    7，移动文件
    （1）方法1

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    let fileManager = NSFileManager.defaultManager()
    let homeDirectory = NSHomeDirectory()
    var error:NSErrorPointer = nil
    let srcUrl = homeDirectory + "/Documents/hangge.txt"
    let toUrl = homeDirectory + "/Documents/moved"
    fileManager.moveItemAtPath(srcUrl, toPath: toUrl, error: error)


    （2）方法2

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    // 定位到用户文档目录
    let manager = NSFileManager.defaultManager()
    let urlForDocument = manager.URLsForDirectory( NSSearchPathDirectory.DocumentDirectory, inDomains:NSSearchPathDomainMask.UserDomainMask)
    let url = urlForDocument[0] as NSURL
    var error:NSErrorPointer = nil
     
    let contentsOfURL = manager.contentsOfDirectoryAtURL(url, includingPropertiesForKeys: nil, options: NSDirectoryEnumerationOptions.SkipsHiddenFiles, error: error);
    let srcUrl = url.URLByAppendingPathComponent("test.txt")
    let toUrl = url.URLByAppendingPathComponent("copyed.txt")
    // 移动srcUrl中的文件（test.txt）到toUrl中（copyed.txt）
    let moveItemSuccess = manager.moveItemAtURL(srcUrl, toURL: toUrl, error: error)

    8，删除文件
    （1）方法1

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    let fileManager = NSFileManager.defaultManager()
    let homeDirectory = NSHomeDirectory()
    var error:NSErrorPointer = nil
    let srcUrl = homeDirectory + "/Documents/hangge.txt"
    fileManager.removeItemAtPath(srcUrl, error: error)


    （2）方法2

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    // 定位到用户文档目录
    let manager = NSFileManager.defaultManager()
    let urlForDocument = manager.URLsForDirectory( NSSearchPathDirectory.DocumentDirectory, inDomains:NSSearchPathDomainMask.UserDomainMask)
    let url = urlForDocument[0] as NSURL
    var error:NSErrorPointer = nil
     
    let contentsOfURL = manager.contentsOfDirectoryAtURL(url, includingPropertiesForKeys: nil, options: NSDirectoryEnumerationOptions.SkipsHiddenFiles, error: error);
    let toUrl = url.URLByAppendingPathComponent("copyed.txt")
    // 删除文档根目录下的toUrl路径的文件（copyed.txt文件）
    let removeItemSuccess = manager.removeItemAtURL(toUrl, error: error)
    println("删除结果: (removeItemSuccess)")

    9，删除目录下所有的文件
    （1）方法1：获取所有文件，然后遍历删除

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    let fileManager = NSFileManager.defaultManager()
    var error:NSErrorPointer = nil
    var myDirectory = NSHomeDirectory() + "/Documents/Files"
    var fileArray:[AnyObject]? = fileManager.subpathsAtPath(myDirectory)
    for fn in fileArray!{
        fileManager.removeItemAtPath(myDirectory + "/(fn)", error: error)
    }


    （2）方法2：删除目录后重新创建该目录

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    let fileManager = NSFileManager.defaultManager()
    var error:NSErrorPointer = nil
    var myDirectory = NSHomeDirectory() + "/Documents/Files"
    fileManager.removeItemAtPath(myDirectory, error: error)
    fileManager.createDirectoryAtPath(myDirectory, withIntermediateDirectories: true,
        attributes: nil, error: error)

    10，读取文件

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    let manager = NSFileManager.defaultManager()
    let urlsForDocDirectory = manager.URLsForDirectory(NSSearchPathDirectory.DocumentDirectory, inDomains:NSSearchPathDomainMask.UserDomainMask)
    let docPath:NSURL = urlsForDocDirectory[0] as NSURL
    let file = docPath.URLByAppendingPathComponent("test.txt")
     
    //方法1
    var readHandler = NSFileHandle(forReadingFromURL:file,error:nil)!
    var data = readHandler.readDataToEndOfFile()
    var readString = NSString(data: data, encoding: NSUTF8StringEncoding)
    println("文件内容: (readString)")
    //方法2
    let data = manager.contentsAtPath(file.path!)
    var readString = NSString(data: data, encoding: NSUTF8StringEncoding)
    println("文件内容: (readString)")

    11，在任意位置写入数据

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    let string = "添加一些文字到文件末尾"
    let appendedData = string.dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: true)
    let writeHandler = NSFileHandle(forWritingToURL:file,error:nil)!
    writeHandler.seekToEndOfFile()
    writeHandler.writeData(appendedData!)

    12，文件权限判断

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    let manager = NSFileManager.defaultManager()
    let urlsForDocDirectory = manager.URLsForDirectory(NSSearchPathDirectory.DocumentDirectory, inDomains:NSSearchPathDomainMask.UserDomainMask)
    let docPath:NSURL = urlsForDocDirectory[0] as NSURL
    let file = docPath.URLByAppendingPathComponent("test.txt")
     
    let readable = manager.isReadableFileAtPath(file.path!)
    println("可读: (readable)")
    let writeable = manager.isWritableFileAtPath(file.path!)
    println("可写: (writeable)")
    let executable = manager.isExecutableFileAtPath(file.path!)
    println("可执行: (executable)")
    let deleteable = manager.isDeletableFileAtPath(file.path!)
    println("可删除: (deleteable)")

    13，获取文件属性（创建时间，修改时间，文件大小，文件类型等信息）

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    let manager = NSFileManager.defaultManager()
    let urlsForDocDirectory = manager.URLsForDirectory(NSSearchPathDirectory.DocumentDirectory, inDomains:NSSearchPathDomainMask.UserDomainMask)
    let docPath:NSURL = urlsForDocDirectory[0] as NSURL
    let file = docPath.URLByAppendingPathComponent("test.txt")
     
    let attributes = manager.attributesOfItemAtPath(file.path!,error:nil) //结果为AnyObject类型
    println("attributes: (attributes!)")

    14，文件/文件夹比较

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    let manager = NSFileManager.defaultManager()
    let urlsForDocDirectory = manager.URLsForDirectory(NSSearchPathDirectory.DocumentDirectory, inDomains:NSSearchPathDomainMask.UserDomainMask)
    let docPath:NSURL = urlsForDocDirectory[0] as NSURL
    let contents = manager.contentsOfDirectoryAtPath(docPath.path!,error:nil)!
     
    //下面比较前面两个文件是否内容相同（该方法也可以用来比较目录）
    let count = contents.count
    if count > 1 {
        let path1 = docPath.path! + "/" + (contents[0] as String)
        let path2 = docPath.path! + "/" + (contents[1] as String)
        let equal = manager.contentsEqualAtPath(path1,andPath:path2)
        println("比较结果: (equal)")
    }
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  • 原文地址：https://www.cnblogs.com/Free-Thinker/p/4838118.html
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