从Dropbox加载/读取txt文件到swift

问题描述

我正在尝试加载具有以下格式的.txt文件

人员 位置 数据 平均值 目标
第一人称董事37 45 80
第二个人助理23 56 34
第三个人CEO 34 45 67

共有五列，第一行是标题。以下是我在viewDidLoad中使用的代码：

---

<nav class="main-nav">
<ul class="main-nav-list">
    <li><a href="#" class="main-nav-link">Books</a></li>
    </li>
    <li>
        <a href="#" class="main-nav-link">About</a>
    </li>
    <li>
        <a href="#" class="main-nav-link">Contact</a>
    </li>
</ul>
</nav>

.main-nav{
grid-column:4/-1;
grid-row:3/4;
position:relative;
}

.main-nav-list{
display:grid;
grid-template-columns: repeat(6,1fr);
grid-template-rows: repeat(3,1fr);
position:relative;
}

.main-nav-link{
text-decoration:none;
text-transform:uppercase;
color:darkolivegreen;
display:grid;
}

.main-nav-link::before,.main-nav-link::after{
content:"";
width:90%;
height:4px;
display:block;
position:absolute;
}

但是，我在下面看到错误消息

override func viewDidLoad() {
    super.viewDidLoad()
    // load txt file from dropBox
    let url = URL(string: "https://www.dropBox.com/s/pr0ldvdeab48mpp/prueba.txt?dl=0")
    let task = URLSession.shared.downloadTask(with: url!) {(urlresponse,response,error) in
        guard let originalURL = urlresponse else { return }
        do {
            // get path to directory
            let path = try FileManager.default.url(for: .documentDirectory,in: .userDomainMask,appropriateFor: nil,create: false)
            // giving name to file
            let newUrl = path.appendingPathComponent("myTextFile")
            // move file from old to new url
            try FileManager.default.moveItem(at: originalURL,to: newUrl)
        } catch { 
            print(error.localizedDescription)
            return
        }
    }
    task.resume()
    //reading the file
    let path = FileManager.default.urls(for: .documentDirectory,in: .userDomainMask).first
    do {
        let fileUrls = try FileManager.default.contentsOfDirectory(at: path!,includingPropertiesForKeys: nil)
        //read the text
        let textContent = try String(contentsOf: fileUrls[0],encoding: .utf8)
        print(textContent)
    } catch {
        print("ERROR")
    }
}

线程1：致命错误：索引超出范围

我的目标是能够在需要时单独读取文件和访问每列/行的元素，但不能识别问题的根源。感谢任何帮助。

注意：如果有帮助，我可以灵活地将文件加载为.csv或其他格式（如果更容易的话）。

解决方法

您的问题是dl = 0并不指向文件。它将指向一个html文件。您需要使用dl = 1才能直接下载文件。您还应该将下载代码从下载任务移到完成封包中。您还可以从url响应中获取文件名。尝试这样：

// load txt file from dropbox (make sure you change the string suffix from dl=0 to dl=1)
let url = URL(string: "https://www.dropbox.com/s/pr0ldvdeab48mpp/prueba.txt?dl=1")!
let task = URLSession.shared.downloadTask(with: url) { location,response,error in
    guard let location = location else { return }
    do {
        // get the documentDirectory url
        let documentDirectory = try FileManager.default.url(for: .documentDirectory,in: .userDomainMask,appropriateFor: nil,create: false)
        print(documentDirectory.path)
        // get the suggested name fro the url response or the url last path component
        let name = (response as? HTTPURLResponse)?.suggestedFilename ?? location.lastPathComponent
        // create a destination url
        let destination = documentDirectory.appendingPathComponent(name)
        // check if the file already exists
        if FileManager.default.fileExists(atPath: destination.path) {
            // remove the file (if you would like to use the new one)
            try FileManager.default.removeItem(at: destination)
        }
        // move file from the temporary location to the destination
        try FileManager.default.moveItem(at: location,to: destination)
        // reading the downloaded file
        let textContent = try String(contentsOf: destination,encoding: .utf8)
        print(textContent)
    } catch {
        print("ERROR")
    }
}
task.resume()