XML string straight to zip file

[sindizzy]

I've been looking through the examples and haven't come across this scenario. Maybe I missed it.
In code I have an XML string and I typically save it to a file n the disk. It ends up being quite large so I want to compress it.
Is there a way for me to take the XML string that is in memory and directly compress it to a zip file, bypassing the save to XML file first and then compressing that file?

[sindizzy]

ok I think I have something based on the sample here:

 var zipFile = Path.ChangeExtension(jsonFile, ".zip");
 var fs = File.Create(zipFile);

 // 'using' statements guarantee the stream is closed properly which is a big source
 // of problems otherwise.  Its exception safe as well which is great.
 using (ZipOutputStream s = new ZipOutputStream(fs))
 {
     s.SetLevel(9); // 0 - store only to 9 - means best compression
     byte[] buffer = new byte[4096];

     var ename = Path.GetFileName(jsonFile);
     var entry = new ZipEntry(ename);

     // Setup the entry data as required.

     // Crc and size are handled by the library for seakable streams so no need to do them here.

     // Could also use the last write time or similar for the file.
     entry.DateTime = DateTime.Now;
     s.PutNextEntry(entry);

     using (Stream ss = jsonStr.ToStream()) // CONVERT JSON STRING TO STREAM
     {
         // Using a fixed size buffer here makes no noticeable difference for output
         // but keeps a lid on memory usage.
         int sourceBytes;
         do
         {
             sourceBytes = ss.Read(buffer, 0, buffer.Length);
             s.Write(buffer, 0, sourceBytes);
         } while (sourceBytes > 0);
     }
 }


// https://stackoverflow.com/questions/1879395/how-do-i-generate-a-stream-from-a-string
public static Stream ToStream(this string str)
{
    MemoryStream stream = new MemoryStream();
    StreamWriter writer = new StreamWriter(stream);
    writer.Write(str);
    writer.Flush();
    stream.Position = 0;
    return stream;
}