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VBScript Intro Lesson 2

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Andrew Husking

Sun Oct 07 2007, 04:40AM

Andrew Husking

[ IT User ]

Joined: Fri Apr 13 2007, 06:36PM
Posts: 23

Time For the next installment of the VBScript intro course, i have been really busy\lazy lately, and i haven't put the next installment up.

So, This time we will look at some really useful things text files, and how to read\write and append to them.....

So lets start with reading a text file

Const ForReading = 1

Set objFSO = CreateObject("Scripting.FileSystemObject")
Set objTextFile = objFSO.OpenTextFile ("c:\Test.txt", ForReading)

Do Until objTextFile.AtEndOfStream
   strText = StrText & objTextFile.Readline & vbCrlf

Loop

Msgbox StrText

ObjTextFile.Close

The First line,
Const ForReading = 1 allows us to tell VBscript what we want to do with the file, we understand it as ForReading, but to it, it knows reading as the number 1.

Set objFSO = CreateObject("Scripting.FileSystemObject")
Creates an object that we can use to interact with the file system, this allows us to create, delete and do a few other things with files, but its going to allow us to open the text file we want so we can read it

Set objTextFile = objFSO.OpenTextFile ("c:\Test.txt", ForReading)

This line opens the text file we want for reading and stores it in an object we can use later

Now, the reading of the text file

Do Until objTextFile.AtEndOfStream
   strText = StrText & objTextFile.Readline & vbCrlf
   Next
Loop

The Do Until ObjTextFile.AtEndOfStream means that it will keep reading until it reaches the end of the text file (the loop command goes with this)

   strText = StrText & objTextFile.Readline & vbCrlf  Means that we are taking the previous lines read from the text file (StrText) adding the new line (ObjTextFile.Readline) and going to a new line (vbcrlf)

msgbox strText just displays what we just read from the text file in a msgbox

Then Lastly we close the text file

And thats how you read from a text file

Now to write to a new text file

Const ForAppending = 8

Set objFSO = CreateObject("Scripting.FileSystemObject")
Set objFile = objFSO.CreateTextFile("C:\Test2.txt")
Set objTextFile = objFSO.OpenTextFile  ("c:\test2.txt", ForAppending, True)

Name = inputbox ("What is your name?")
Age = InputBox ("how old are you?")
ObjtextFile.Writeline( name & " is " & age & " years old!" & vbcrlf)
objTextFile.Close

now for the break down...

Const ForAppending = 8, Basically the same as ForReading, we are assigning a String that we can understand to the number the computer understands

Again we create the FileSystem object using

Set objFSO = CreateObject("Scripting.FileSystemObject")

Now, this is a unique way of doing it, but it still works nicely

Set objFile = objFSO.CreateTextFile("C:\Test2.txt")
Set objTextFile = objFSO.OpenTextFile  ("c:\test2.txt", ForAppending, True)

We are creating the new text file using the first line, then opening the text file for appending instead of writing, you can use code to just open it for writing but for this example i chose the creating then appending.

the second line just opens the text file for appending

Now for the last bit

Name = inputbox ("What is your name?")
Age = InputBox ("how old are you?")
ObjtextFile.Writeline( name & " is " & age & " years old!" & vbcrlf)
objTextFile.Close

First we ask the user for some data to put into the text file (name and age), then we write that to a text file using  ObjtextFile.Writeline( name & " is " & age & " years old!" & vbcrlf)
Then Lastly we close the text file

And thats how you Write to a new text file, if you want to append, change the filename to a file that exists already and remove the line: "set objFile = objFSO.CreateTextFile("C:\Test2.txt") "

And thats about it this time, short and sweet i guess, post any questions comments you have...

Cheers Andrew

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Andrew Husking
ERH Software Developer
IT Admin, Hobby Programmer
Microsoft Registered Partner

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