How to read an certain line from text file with UWP app?

Question

How do I read for example only the second line from text file containing of four lines located on the Windows Phone SD card or internal storage with UWP app coded in Visual C#?

Does internal storage mean the same as Computer\Windows phone\Phone in Explorer?

Answer 1

Since there are not a lot of details in your question I will assume the file you need is deployed with the application.

public async Task<string> ReadLine(int lineIndex)
{
    var path = @"test.txt";
    var folder = Windows.ApplicationModel.Package.Current.InstalledLocation;
    var file = await folder.GetFileAsync(path);
    var lines = await Windows.Storage.FileIO.ReadLinesAsync(file);
    if (lines.Count >= lineIndex + 1)
    {
        return line[lineIndex];
    }
    else
    {
       return null;
    }
}

If the file is not deployed with the app, change the folder property to another one from here: Windows.Storage.ApplicationData.Current. (LocalFolder, TempFolder, RoamingFolder)