Read text file with progress reporting

TextReader.cs

using System.Threading.Tasks;

public class TextReader
{
    public double Percentage { get; set; }

    public async Task ReadAsync(string filePath)
    {
        var progress = new Progress<(double current, double total)>();
        progress.ProgressChanged += (_, e) => Percentage = e.current / e.total;

        await ReadTextAsync(filePath, progress);
    }

    public static async Task<string> ReadTextAsync(string filePath, IProgress<(double current, double total)> progress)
    {
        using var stream = new FileStream(filePath, FileMode.Open, FileAccess.Read);
        using var reader = new StreamReader(stream);

        var readTask = reader.ReadToEndAsync();

        var progressTask = Task.Run(async () =>
        {
            while (stream.Position < stream.Length)
            {
                await Task.Delay(TimeSpan.FromMilliseconds(100));
                progress.Report((stream.Position, stream.Length));
            }
        });

        await Task.WhenAll(readTask, progressTask);

        return readTask.Result;
    }
}