Swift

iOS FileManager 文件及文件夹处理

Posted Cola🌀
FileManager
1. 获取用户文档目录路径
let manager = FileManager.default
var documentsURL = manager.urls(for: .documentDirectory, in: .userDomainMask)[0]
2. 搜索
  • 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.contentsOfDirectory(atPath: documentsURL.path)

print("contentsOfPath: \(contentsOfPath)")
  • 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.contentsOfDirectory(at: url, includingPropertiesForKeys: nil, options: .skipsHiddenFiles)

print("contentsOfURL: \(contentsOfURL)")
  • 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.enumerator(atPath: url.path)

print("enumeratorAtPath: \(enumeratorAtPath?.allObjects)")
  • 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.enumerator(at: url, includingPropertiesForKeys: nil, options: .skipsHiddenFiles, errorHandler:nil)

print("enumeratorAtURL: \(enumeratorAtURL?.allObjects)")
  • 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.subpaths(atPath: url.path)

print("subPaths: \(subPaths)")
3. 判断文件或文件夹是否存在
let filePath:String = NSHomeDirectory() + "/Documents/test.txt"

let exist = manager.fileExists(atPath: filePath)
4. 创建文件夹
let myDirectory:String = NSHomeDirectory() + "/Documents/myFolder/Files"

// 方法1
try! manager.createDirectory(atPath: myDirectory, withIntermediateDirectories: true, attributes: nil)
// 方法2
let folder = baseUrl.appendingPathComponent(name, isDirectory: true)
let exist = manager.fileExists(atPath: folder!.path)
if !exist {
    try! manager.createDirectory(at: folder!, withIntermediateDirectories: true, attributes: nil)
}
5. 在文档目录下新建folder目录
let urlForDocument = manager.urls(for: .documentDirectory, in: .userDomainMask)

let url = urlForDocument[0] as NSURL

createFolder(name: "folder", baseUrl: url)
6. 将对象写入文件

可以通过write(to:)方法，可以创建文件并将对象写入，对象包括String，NSString，UIImage，NSArray，NSDictionary等。

  • 把String保存到文件
let filePath:String = NSHomeDirectory() + "/Documents/test.txt"

let info = "Hello World!"

try! info.write(toFile: filePath, atomically: true, encoding: String.Encoding.utf8)
  • 把图片保存到文件路径下
let filePath = NSHomeDirectory() + "/Documents/test.png"

let image = UIImage(named: "apple.png")

let data:Data = UIImagePNGRepresentation(image!)!

try? data.write(to: URL(fileURLWithPath: filePath))
  • 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.write(toFile: filePath, atomically: true)
  • 把NSDictionary保存到文件路径下
let dictionary:NSDictionary = ["Gold": "1st Place", "Silver": "2nd Place"]

let filePath:String = NSHomeDirectory() + "/Documents/dictionary.plist"

dictionary.write(toFile: filePath, atomically: true)
7. 创建文件
func createFile(name:String, fileBaseUrl:URL){
    let manager = FileManager.default
    let file = fileBaseUrl.appendingPathComponent(name)
    print("文件: \(file)")

    let exist = manager.fileExists(atPath: file.path)
    if !exist {
        let data = Data(base64Encoded:"aGVsbG8gd29ybGQ=" ,options:.ignoreUnknownCharacters)
        let createSuccess = manager.createFile(atPath: 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 urlForDocument = manager.urls( for: .documentDirectory, in:.userDomainMask)

let url = urlForDocument[0]

createFile(name:"test.txt", fileBaseUrl: url)
// 或者：createFile(name: "folder/new.txt", fileBaseUrl: url)
8. 复制文件
  • 方法1
let fileManager = FileManager.default

let homeDirectory = NSHomeDirectory()

let srcUrl = homeDirectory + "/Documents/test.txt"

let toUrl = homeDirectory + "/Documents/copyed.txt"

try! fileManager.copyItem(atPath: srcUrl, toPath: toUrl)
  • 方法2
// 定位到用户文档目录
let manager = FileManager.default
let urlForDocument = manager.urls( for:.documentDirectory, in:.userDomainMask)
let url = urlForDocument[0]

// 将test.txt文件拷贝到文档目录根目录下的copyed.txt文件
let srcUrl = url.appendingPathComponent("test.txt")
let toUrl = url.appendingPathComponent("copyed.txt")
try! manager.copyItem(at: srcUrl, to: toUrl)
9. 移动文件
  • 方法1
let fileManager = FileManager.default

let homeDirectory = NSHomeDirectory()

let srcUrl = homeDirectory + "/Documents/test.txt"

let toUrl = homeDirectory + "/Documents/moved/test.txt"

try! fileManager.moveItem(atPath: srcUrl, toPath: toUrl)
  • 方法2
// 定位到用户文档目录
let manager = FileManager.default
let urlForDocument = manager.urls( for: .documentDirectory, in:.userDomainMask)
let url = urlForDocument[0]
        
let srcUrl = url.appendingPathComponent("test.txt")
let toUrl = url.appendingPathComponent("copyed.txt")

// 移动srcUrl中的文件（test.txt）到toUrl中（copyed.txt）
try! manager.moveItem(at: srcUrl, to: toUrl)
10. 删除文件
  • 方法1
let fileManager = FileManager.default

let homeDirectory = NSHomeDirectory()

let srcUrl = homeDirectory + "/Documents/test.txt"

try! fileManager.removeItem(atPath: srcUrl)
  • 方法2
// 定位到用户文档目录
let manager = FileManager.default
let urlForDocument = manager.urls(for: .documentDirectory, in:.userDomainMask)
let url = urlForDocument[0]
let toUrl = url.appendingPathComponent("copyed.txt")

// 删除文档根目录下的toUrl路径的文件（copyed.txt文件）
try! manager.removeItem(at: toUrl)
11. 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 = FileManager.default

let myDirectory = NSHomeDirectory() + "/Documents/Files"

let fileArray = fileManager.subpaths(atPath: myDirectory)

for fn in fileArray!{
    try! fileManager.removeItem(atPath: myDirectory + "/\(fn)")
}
  • 方法2：删除目录后重新创建该目录
let fileManager = FileManager.default

let myDirectory = NSHomeDirectory() + "/Documents/Files"

try! fileManager.removeItem(atPath: myDirectory)

try! fileManager.createDirectory(atPath: myDirectory, withIntermediateDirectories: true, attributes: nil)
12. 读取文件
let manager = FileManager.default

let urlsForDocDirectory = manager.urls(for: .documentDirectory, in:.userDomainMask)

let docPath = urlsForDocDirectory[0]

let file = docPath.appendingPathComponent("test.txt")

// 方法1

let readHandler = try! FileHandle(forReadingFrom:file)

let data = readHandler.readDataToEndOfFile()

let readString = String(data: data, encoding: String.Encoding.utf8)

print("文件内容: \(readString)")

// 方法2

let data2 = manager.contents(atPath: file.path)

let readString2 = String(data: data2!, encoding: String.Encoding.utf8)

print("文件内容: \(readString2)")
13. 在任意位置写入数据
let manager = FileManager.default

let urlsForDocDirectory = manager.urls(for:.documentDirectory, in:.userDomainMask)

let docPath = urlsForDocDirectory[0]

let file = docPath.appendingPathComponent("test.txt")

let string = "添加一些文字到文件末尾"

let appendedData = string.data(using: String.Encoding.utf8, allowLossyConversion: true)

let writeHandler = try? FileHandle(forWritingTo:file)

writeHandler!.seekToEndOfFile()

writeHandler!.write(appendedData!)
14. 文件权限判断
let manager = FileManager.default

let urlForDocument = manager.urls(for: .documentDirectory, in:.userDomainMask)

let docPath = urlForDocument[0]

let file = docPath.appendingPathComponent("test.txt")

let readable = manager.isReadableFile(atPath: file.path)

print("可读: \(readable)")

let writeable = manager.isWritableFile(atPath: file.path)

print("可写: \(writeable)")

let executable = manager.isExecutableFile(atPath: file.path)

print("可执行: \(executable)")

let deleteable = manager.isDeletableFile(atPath: file.path)

print("可删除: \(deleteable)")
15. 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 = FileManager.default

let urlForDocument = manager.urls(for: .documentDirectory, in:.userDomainMask)

let docPath = urlForDocument[0]

let file = docPath.appendingPathComponent("test.txt")

let attributes = try? manager.attributesOfItem(atPath: file.path) //结果为Dictionary类型

print("attributes: \(attributes!)")

// 从 attributes 中获取具体的属性：

print("创建时间：\(attributes![FileAttributeKey.creationDate]!)")

print("修改时间：\(attributes![FileAttributeKey.modificationDate]!)")

print("文件大小：\(attributes![FileAttributeKey.size]!)")
16. 文件/文件夹比较
let manager = FileManager.default

let urlForDocument = manager.urls(for: .documentDirectory, in:.userDomainMask)

let docPath = urlForDocument[0]

let contents = try! manager.contentsOfDirectory(atPath: docPath.path)

// 下面比较用户文档中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.contentsEqual(atPath: path1,andPath:path2)

    print("path1：\(path1)")

    print("path2：\(path2)")

    print("比较结果： \(equal)")

}
参考文献