Stupid smart code
time to read 3 min | 549 words

We had the following code:

public static void WriteDataToRequest(HttpWebRequest req, string data)
{
    var byteArray = Encoding.UTF8.GetBytes(data);

    req.ContentLength = byteArray.Length;

    using (var dataStream = req.GetRequestStream())
    {
        dataStream.Write(byteArray, 0, byteArray.Length);
        dataStream.Flush();
    }
}

And that is a problem, because it allocates the memory twice, once for the string, once for the buffer. I changed that to this:

public static void WriteDataToRequest(HttpWebRequest req, string data)
{
    var byteCount = Encoding.UTF8.GetByteCount(data);
    req.ContentLength = byteCount;
    using (var dataStream = req.GetRequestStream())
    {
        if(byteCount <= 0x1000) // small size, just let the system allocate it
        {
            var bytes = Encoding.UTF8.GetBytes(data);
            dataStream.Write(bytes, 0, bytes.Length);
            dataStream.Flush();
            return;
        }

        var buffer = new byte[0x1000];
        var maxCharsThatCanFitInBuffer = buffer.Length / Encoding.UTF8.GetMaxByteCount(1);
        var charBuffer = new char[maxCharsThatCanFitInBuffer];
        int start = 0;
        var encoder = Encoding.UTF8.GetEncoder();
        while (start < data.Length)
        {
            var charCount = Math.Min(charBuffer.Length, data.Length - start);

            data.CopyTo(start, charBuffer, 0, charCount);
            var bytes = encoder.GetBytes(charBuffer, 0, charCount, buffer, 0, false);
            dataStream.Write(buffer, 0, bytes);
            start += charCount;
        }
        dataStream.Flush();
    }
}

And I was quite proud of myself.

Then I realized that I was stupid. Why?

Tweet Share Share 49 comments
Tags: