在代码中为Mac OS X上的给定文件扩展名设置默认应用程序

import Foundation
import LaunchServices

func setDefaultApplication(forExtension ext: String, bundleID: String) -> Bool {
    let ext = ext as CFString
    let bundleID = bundleID as CFString
    let error = LSSetDefaultHandlerForURLScheme(ext, bundleID)
    return error == noErr
}

let extension = "txt"
let bundleID = "com.apple.TextEdit"
let success = setDefaultApplication(forExtension: extension, bundleID: bundleID)

if success {
    print("成功设置\(extension)文件的默认应用为\(bundleID)")
} else {
    print("设置失败")
}

import Foundation

func setDefaultApplication(forExtension ext: String, bundleID: String) -> Bool {
    let task = Process()
    task.launchPath = "/usr/bin/duti"
    task.arguments = ["-s", bundleID, ext]
    task.launch()
    task.waitUntilExit()
    return task.terminationStatus == 0
}

let extension = "txt"
let bundleID = "com.apple.TextEdit"
let success = setDefaultApplication(forExtension: extension, bundleID: bundleID)

if success {
    print("成功设置\(extension)文件的默认应用为\(bundleID)")
} else {
    print("设置失败")
}