你可以尝试创建一个用于打开和保存文件的类:
编辑/更新:Swift 5或更高版本
class File {
class func open(
_ path: String,
encoding: String.Encoding = .utf8
) throws -> String {
guard FileManager.default.fileExists(atPath: path) else {
throw NSError(
domain: "NSCocoaErrorDomain",
code: 260,
userInfo: [
"NSUnderlyingError": #"Error Domain=NSPOSIXErrorDomain Code=2 "No such file or directory""#,
"NSFilePath": path
]
) as Error
}
return try String(
contentsOfFile: path,
encoding: encoding
)
}
class func save(
_ path: String,
_ content: String,
encoding: String.Encoding = .utf8
) throws {
try content.write(
toFile: path,
atomically: true,
encoding: encoding
)
}
}
用法:File.save
let stringToSave: String = "Your text"
if let fileURL = FileManager.default.urls(
for: .desktopDirectory,
in: .userDomainMask
).first?.appendingPathComponent("file.txt") {
do {
try File.save(fileURL.path, stringToSave)
print("file saved")
} catch {
print("Error saving file:", error)
}
}
用法:File.open
if let fileURL = FileManager.default.urls(
for: .desktopDirectory,
in: .userDomainMask
).first?.appendingPathComponent("file.txt") {
do {
let loadedText = try File.open(fileURL.path)
print("Loaded text:", loadedText)
} catch {
print("Error reading file:", error)
}
}
或者,如果您更喜欢扩展StringProtocol
:
extension StringProtocol {
func open(from directory: FileManager.SearchPathDirectory = .documentDirectory,
in domain: FileManager.SearchPathDomainMask = .userDomainMask,
encoding: String.Encoding = .utf8) throws -> String {
let directory = try FileManager.default.url(
for: directory,
in: domain,
appropriateFor: nil,
create: true
)
return try String(
contentsOf: directory.appendingPathComponent(.init(self)),
encoding: encoding
)
}
func save(as fileName: String,
to directory: FileManager.SearchPathDirectory = .documentDirectory,
in domain: FileManager.SearchPathDomainMask = .userDomainMask,
encoding: String.Encoding = .utf8) throws {
let directory = try FileManager.default.url(
for: directory,
in: domain,
appropriateFor: nil,
create: true
)
try write(to: directory.appendingPathComponent(fileName),
atomically: true,
encoding: encoding)
}
}
iOS使用方法(保存/加载到文档目录):
let stringToSave: String = "Your text"
let fileName = "file.txt"
do {
try stringToSave.save(as: fileName)
print("Text saved!!!")
let loadedText = try fileName.open()
print("Text loaded:", loadedText)
} catch {
print("Error:", error)
}
使用 macOS(保存/加载桌面目录):
let string = "Your text"
let fileName = "file.txt"
do {
try string.save(as: fileName, to: .desktopDirectory)
print("Text saved!!!")
let loadedText = try fileName.open(from: .desktopDirectory)
print("Text loaded:", loadedText)
} catch {
print("Error:", error)
}
println
的游乐场输出与控制台输出不相等。有关控制台的更多信息,请参见此问题。 - alttag