Question

上下文 我有一个应用程序，用户可以在其中编写多个“场景”。这些文件另存为单独的文件。我需要为用户提供2个导出选项（将所有场景单独导出或全部导出到一个主文件中）。

我要做什么目前，我的方法是尝试检索扩展名为.rtf的每个文件的URL。然后遍历每个对象，提取NSAttributedString。最后，我计划依次将每个文件写入一个主.rtf文件。

我尝试过的事情在类似问题上使用其他答案（例如here和here）的想法，我正在尝试以下我已注释清楚的内容。不用说我对下一步的工作感到困惑和迷茫：

@IBAction func exportPressed(_ sender: Any) {
        //THIS BIT RETRIEVES THE URLS OF EACH .RTF FILE AND PUTS THEM INTO AN ARRAY CALLED SCENEURLS. THIS BIT WORKS FINE AND I'VE TESTED BY PRINTING OUT A LIST OF THE URLS.

        do {
            let documentsURL = getDocumentDirectory()
            let docs = try FileManager.default.contentsOfDirectory(at: documentsURL, includingPropertiesForKeys: [], options:  [.skipsHiddenFiles, .skipsSubdirectoryDescendants])
            let scenesURLs = docs.filter{ $0.pathExtension == "rtf" }

//THIS BIT TRYS TO RETURN THE NSATTRIBUTEDSTRING FOR EACH OF THE SCENE URLS. THIS BIT THROWS UP MULTIPLE ERRORS. I SUPPOSE I WOULD WANT TO ADD THE STRINGS TO A NEW ARRAY [SCENETEXTSTRINGS] SO I COULD THEN LOOP THROUGH THAT AND WRITE THE NEW MASTER FILE WITH TEXT FROM EACH IN THE RIGHT ORDER.

            scenesURLs.forEach {_ in

                return try NSAttributedString()(url: scenesURLs(),
                                                options: [.documentType: NSAttributedString.DocumentType.rtf],
                                                documentAttributes: nil)
            } catch {

                print("failed to populate text view with current scene with error: \(error)")

                return nil
            }
            }
        } catch {
            print(error)
        }

//THERE NEEDS TO BE SOMETHING HERE THAT THEN WRITES THE STRINGS IN THE NEW STRINGS ARRAY TO A NEW MASTER FILE
    }

首先，我只需要一些如何获取数组中的字符串的帮助-之后，我可以尝试编写新的母版！

Answer 1

如果要从文件URL数组中获取NSAttributedString数组，则可以使用map代替forEach。您还需要解决一些语法问题。

将forEach的使用替换为：

let attributedStrings = scenesURLs.compactMap { (url) -> NSAttributedString? in
    do {
        return try NSAttributedString(url: url, options: [.documentType: NSAttributedString.DocumentType.rtf], documentAttributes: nil)
    } catch {
        print("Couldn't load \(url): \(error)")
        return nil
    }
}

如果您不关心记录错误，可以将其简化为：

let attributedStrings = scenesURLs.compactMap {
    return try? NSAttributedString(url: $0, options: [.documentType: NSAttributedString.DocumentType.rtf], documentAttributes: nil)
}

要从数组中创建一个最终的NSAttributedString，您可以执行以下操作：

let finalAttributedString = attributedStrings.reduce(into: NSMutableAttributedString()) { $0.append($1) }

从目录中的所有rtf文件中读取文本，并创建主文件swift

1 个答案: