Question

在OS X Finder中有评论＆＃39;文件属性。可以通过添加“评论”来查找它。右键单击文件或文件夹并选择“获取信息”后的列或编辑/选中。

如何在swift或objective-c中读取此值？

我已经检查了NSURL，但似乎没有一个是正确的

Answer 1

请勿使用低级扩展属性API来读取Spotlight元数据。为此提供了适当的Spotlight API。（它被称为文件元数据API。）不仅令人痛苦，还不能保证Apple会继续使用相同的扩展属性来存储这些信息。

使用MDItemCreateWithURL()为文件创建MDItem。将MDItemCopyAttribute()与kMDItemFinderComment一起使用，即可获取该项目的Finder评论。

Answer 2

将各个部分放在一起（Ken Thomases阅读上面的答案并撰写答案link）您可以使用带有getter和setter的计算属性扩展URL，以便对文件进行读/写注释：

更新： Xcode 8.2.1•Swift 3.0.2

extension URL {
    var finderComment: String? {
        get {
            guard isFileURL else { return nil }
            return MDItemCopyAttribute(MDItemCreateWithURL(kCFAllocatorDefault, self as CFURL), kMDItemFinderComment) as? String
        }
        set {
            guard isFileURL, let newValue = newValue else { return }
            let script = "tell application \"Finder\"\n" +
                String(format: "set filePath to \"%@\" as posix file \n", absoluteString) +
                String(format: "set comment of (filePath as alias) to \"%@\" \n", newValue) +
            "end tell"
            guard let appleScript = NSAppleScript(source: script) else { return }
            var error: NSDictionary?
            appleScript.executeAndReturnError(&error)
            if let error = error {
                print(error[NSAppleScript.errorAppName] as! String)
                print(error[NSAppleScript.errorBriefMessage] as! String)
                print(error[NSAppleScript.errorMessage] as! String)
                print(error[NSAppleScript.errorNumber] as! NSNumber)
                print(error[NSAppleScript.errorRange] as! NSRange)
            }
        }
    }
}

Xcode 7.3.1•Swift 2.2.1

extension NSURL {
    var finderComment: String? {
        get {
            guard fileURL else { return nil }
            return MDItemCopyAttribute(MDItemCreateWithURL(kCFAllocatorDefault, self), kMDItemFinderComment) as? String
        }
        set {
            guard let newValue = newValue where fileURL else { return }
            let script = "tell application \"Finder\"\n" +
                         String(format: "set filePath to \"%@\" as posix file \n", absoluteString) +
                         String(format: "set comment of (filePath as alias) to \"%@\" \n", newValue) +
                         "end tell"
            guard let appleScript = NSAppleScript(source: script) else { return }
            var error: NSDictionary?
            appleScript.executeAndReturnError(&error)
            if let error = error {
                print(error[NSAppleScriptErrorAppName] as! String)
                print(error[NSAppleScriptErrorBriefMessage] as! String)
                print(error[NSAppleScriptErrorMessage] as! String)
                print(error[NSAppleScriptErrorNumber] as! NSNumber)
                print(error[NSAppleScriptErrorRange] as! NSRange)
            }
        }
    }
}

如何阅读文件注释字段

2 个答案: