swift小技巧之文件，文件夹操作大全

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

//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

  • （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 = try? manager.contentsOfDirectoryAtPath(url.path!)
//contentsOfPath：Optional([fold1, test1.txt])
print ( "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 = try? manager.contentsOfDirectoryAtURL(url, includingPropertiesForKeys:  nil , options:  NSDirectoryEnumerationOptions . SkipsHiddenFiles );
//contentsOfURL：Optional([file://Users/.../Application/.../Documents/fold1/,
// file://Users/.../Application/.../Documents/test1.txt])
print ( "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])
print ( "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])
print ( "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])
print ( "subPaths: \(subPaths)" )

2，判断文件或文件夹是否存在

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：

    let  myDirectory: String  =  NSHomeDirectory () +  "/Documents/myFolder/Files"
let  fileManager =  NSFileManager .defaultManager()
//withIntermediateDirectories为ture表示路径中间如果有不存在的文件夹都会创建
try! fileManager.createDirectoryAtPath(myDirectory,
     withIntermediateDirectories:  true , attributes:  nil )

  • 方式2：

    func  createFolder(name: String ,baseUrl: NSURL ){
     let  manager =  NSFileManager .defaultManager()
     let  folder = baseUrl. URLByAppendingPathComponent (name, isDirectory:  true )
     print ( "文件夹: \(folder)" )
     let  exist = manager.fileExistsAtPath(folder.path!)
     if  !exist {
         try! manager.createDirectoryAtURL(folder, withIntermediateDirectories:  true , attributes:  nil )
     }
}
 
//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
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

    let  filePath: String  =  NSHomeDirectory () +  "/Documents/hangge.txt"
let  info =  "欢迎来到hange.com"
try! info.writeToFile(filePath, atomically:  true , encoding:  NSUTF8StringEncoding )

  • （2）把图片保存到文件路径下

    let  filePath: String  =  NSHomeDirectory () +  "/Documents/hangge.png"
let  image =  UIImage (named:  "apple.png" )
let  data: NSData  =  UIImagePNGRepresentation (image!)!
data.writeToFile(filePath, atomically:  true )

  • （3）把NSArray保存到文件路径下

    let  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

    let  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

func  createFile(name: String ,fileBaseUrl: NSURL ){
     let  manager =  NSFileManager .defaultManager()
     let  file = fileBaseUrl. URLByAppendingPathComponent (name)
     print ( "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 )
         print ( "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
createFile( "test.txt" , fileBaseUrl: url)
//createFile("folder/new.txt", fileBaseUrl: url)

6，复制文件 

  • 方法1

    // 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
// 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" )
try! manager.copyItemAtURL(srcUrl, toURL: toUrl)

  • 方法2

    let  fileManager =  NSFileManager .defaultManager()
let  homeDirectory =  NSHomeDirectory ()
let  srcUrl = homeDirectory +  "/Documents/hangge.txt"
let  toUrl = homeDirectory +  "/Documents/copyed.txt"
try! fileManager.copyItemAtPath(srcUrl, toPath: toUrl)

7，移动文件 

  • 方法1

    let  fileManager =  NSFileManager .defaultManager()
let  homeDirectory =  NSHomeDirectory ()
let  srcUrl = homeDirectory +  "/Documents/hangge.txt"
let  toUrl = homeDirectory +  "/Documents/moved"
try! fileManager.moveItemAtPath(srcUrl, toPath: toUrl)

  • 方法2

    // 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
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）
try! manager.moveItemAtURL(srcUrl, toURL: toUrl)

8，删除文件 

  • 方法1

    let  fileManager =  NSFileManager .defaultManager()
let  homeDirectory =  NSHomeDirectory ()
let  srcUrl = homeDirectory +  "/Documents/hangge.txt"
try! fileManager.removeItemAtPath(srcUrl)

  • 方法2

    // 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
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）
try! manager.removeItemAtURL(toUrl)

9，删除目录下所有的文件

  • 方法1：获取所有文件，然后遍历删除

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

  • 方法2：删除目录后重新创建该目录

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

10，读取文件

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

    let  readHandler = try!  NSFileHandle (forReadingFromURL:file)
let  data = readHandler.readDataToEndOfFile()
let  readString =  NSString (data: data, encoding:  NSUTF8StringEncoding )
print ( "文件内容: \(readString)" )

  • 方法2

    let  data = manager.contentsAtPath(file.path!)
let  readString =  NSString (data: data!, encoding:  NSUTF8StringEncoding )
print ( "文件内容: \(readString)" )

11，在任意位置写入数据

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

12，文件权限判断

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!)
print ( "可读: \(readable)" )
let  writeable = manager.isWritableFileAtPath(file.path!)
print ( "可写: \(writeable)" )
let  executable = manager.isExecutableFileAtPath(file.path!)
print ( "可执行: \(executable)" )
let  deleteable = manager.isDeletableFileAtPath(file.path!)
print ( "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）

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 = try? manager.attributesOfItemAtPath(file.path!)  //结果为AnyObject类型
print ( "attributes: \(attributes!)" )

14，文件/文件夹比较

let  manager =  NSFileManager .defaultManager()
let  urlsForDocDirectory = manager.URLsForDirectory(NSSearchPathDirectory.DocumentDirectory,inDomains: NSSearchPathDomainMask.UserDomainMask)
let  docPath: NSURL  = urlsForDocDirectory[0]  as  NSURL
let  contents = try! manager.contentsOfDirectoryAtPath(docPath.path!)
//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)
    print ( "比较结果: \(equal)" )
}

posted on 2022-09-29 13:54  梁飞宇  阅读(826)  评论(0)    收藏  举报