Question

我有以下代码写入文件末尾。但是，如何修改行为，以使其创建“ output.txt”（如果不存在）？

谢谢！

func writeFile(){

    let str = "\n" + nominationKeyForWhenCellSelected! + "," + "1"
    let datafromString = str.data(using: String.Encoding.utf8)
    let filename = getDocumentsDirectory().appendingPathComponent("output.txt")


    do {
        let fileHandle = try FileHandle(forWritingTo: filename)
        fileHandle.seekToEndOfFile()
        fileHandle.write(datafromString!)

    } catch {

    }
}

Answer 1

使用FileManager检查文件是否存在。如果没有，只需写数据，否则按您的做法追加。但是不要忘记关闭文件句柄。

do {
    if FileManager.default.fileExists(atPath: filename.path) {
        let fileHandle = try FileHandle(forWritingTo: filename)
        fileHandle.seekToEndOfFile()
        fileHandle.write(datafromString!)
        fileHandle.closeFile()
    } else {
        datafromString.write(to: filename)
    }
} catch {
    print(error)
}

如果不存在，如何在documents文件夹中创建文件？

1 个答案: