TextInputStream and TextOutputStream

General
1

I want to read in a text file and then append data to the end of it.
Do I use TextInputStream to read it, close it, then use TextOutputStream to write it?

2

You may look at BinaryStream, if that will work for you. It has an open method that will allow opening in r/w mode. http://documentation.xojo.com/index.php/BinaryStream.Open

3

or if it is just “plain text” you can append to it without having to read the whole thing

SUB myLog(msg as string)
  Dim f As FolderItem
  Dim t As TextOutputStream
  f=<path to your text file>
  If Not f.exists Then
    t=TextOutputStream.Create(f)
  Else
    t=TextOutputStream.Append(f)
  End If
  t.write msg+EndOfLine
  t.close
END SUB
4

You don’t need the “if”, Append will create the file if it doesn’t exist. You can also use WriteLine instead of “msg+EndOfLine”.

5

WriteLine instead of Write
except is uses the wrong EndofLine character (or it used to at least)

6

You can set the TextOutputStream.Delimiter property.

7

Also, don’t forget that Create and Append will throw an exception is there’s an error and that you should have Exception handlers for an IOException surrounding your code.