收益回报与尝试捕捞，我如何解决它

I've a piece of code:

我有一段代码:

using (StreamReader stream = new StreamReader(file.OpenRead(), Encoding))
{
    char[] buffer = new char[chunksize];
    while (stream.Peek() >= 0)
    {
       int readCount = stream.Read(buffer, 0, chunksize);

       yield return new string(buffer, 0, readCount);
    }
 }
using (Stream