The textbox has a Lines property that returns an array of strings, each string corresponding to the current line...
For Each str As String In TextBox1.Lines
' Do whatever you want with the line...
End If
Best regards,
Johan Stenberg
Lines is an array - to you can reference the specific line you want rath than simply iterating through it.
Textbox.Lines property
http://msdn2.microsoft.com/en-us/library/system.windows.forms.textboxbase.lines.aspx
Example
Dim tempArray() as String
tempArray = textBox1.Lines
Dim s as string = temparray(0) '//Will show first line contents
s = temparray(1) '//Will show second line contents