VS 2005 Fixed Length Of Variables

I am doing an output to a text file using

Code:

StreamWriter.WriteLine(myText)

The file get's created and records are written. Now, the problem is that this needs to be a fixed length text file. I am reading data retrieved from a stored procedure and looping through a data table to populate the text file like:

Code:

Code:

For Each Row In myDataTable.Rows
myText = myDataTable.Rows(i).Item(0).ToString() & _
myDataTable.Rows(i).Item(1).ToString() & _

get a fixed length regardless what is filled from my data table?