While Loop Question

[SIMIN]

Hi all,

How do you open a text file and use a WHILE loop to read all lines, one by one?

Dim MyReader As New StreamReader("C:\File.txt")
While MyReader.ReadLine IsNot Nothing
   'How should I get each line here?
End While

[Nate Bross]

I think this should work [not compiler tested]

 

' you'll want to find the correct property name
While MyReader.EOF = False
   ...
   MyReader.ReadLine()
Loop

[snarfblam]

If it helps, there is also the System.IO.File.ReadAllLines() method.

[Nate Bross]

I suppose that begs the question which is faster and more readable?

 

Dim myData as String() = System.IO.File.ReadAllLines(...);

 

vs.

 

' you'll want to find the correct property name
While MyReader.EOF = False
   ...
   MyReader.ReadLine()
Loop

 

As for myself, I tend to go with the first one since I think it is more readable and for me I time is generally not a concern when processing files line by line.

Edited August 28, 2008 by Nate Bross

[snarfblam]

The former should look a little more like the following:

Dim myLines As String() = System.IO.File.ReadAllLines(filename)

(Assuming that we are using .Net 2.0 or higher)