Further fun hosting IronPython

When I first got my Python host working, I could type expressions and they would run...but I couldn't see the output.  I had to dig a little bit, but found that Python was sending its output to sys.stdout, which at startup is set to a PythonFile wrapping .NET's Console.  To get what I wanted, I need to set sys.stdout to go back to my TextBox.  To do this I added a couple of lines you've already seen.  In the ConsolePane class, I wrote this:

TextBoxStream stream = new TextBoxStream(this.textBox);

this.processor = new PythonProcessor(stream);

and then in the PythonProcessor ctor, I set stdout:

sys.stdout = new PythonFile(outputStream, "w", false);

Then things worked nicely.  Of course I had to write the TextBoxStream class.  Fortunately, it only needed to write.  Here's that code:

 namespace AddInConsole
{
  using System;
   using System.Globalization;
 using System.IO;
    using System.Text;
  using System.Windows;
   using System.Windows.Controls;
  using System.Windows.Input;
 class TextBoxStream : Stream
    {
       private TextBox textBox = null;
     public TextBoxStream(TextBox textBox)
       {
           this.textBox = textBox;
     }

       public override bool CanRead
        {
           get { return false; }
       }

       public override bool CanSeek
        {
           get { return false; }
       }

       public override bool CanWrite
       {
           get { return true; }
        }

       public override void Flush()
        {
           // Do nothing
       }

       public override long Length
     {
           get { return this.textBox.Text.Length; }
        }

       public override long Position
       {
           get
         {
               return this.textBox.CaretIndex;
         }
           set
         {
               throw new NotImplementedException("The method or operation is not implemented.");
           }
       }

       public override int Read(byte[] buffer, int offset, int count)
      {
           throw new NotImplementedException("Read not implemented");
      }

       public override long Seek(long offset, SeekOrigin origin)
       {
           throw new NotImplementedException("The method or operation is not implemented.");
       }

       public override void SetLength(long value)
      {
           throw new NotImplementedException("The method or operation is not implemented.");
       }

       public override void Write(byte[] buffer, int offset, int count)
        {
           // IronPython uses Encoding.ASCII to write to a stream...so we'll pull it back out
          // the same way
         byte[] convertBuffer = new byte[count];
         Array.Copy(buffer, offset, convertBuffer, 0, count);
            string output = Encoding.ASCII.GetString(convertBuffer);
            this.textBox.AppendText(output);
        }
   }
}

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