QTP File Handling

Many a times you may need to interact with text files using QTP. Interaction can be(but not limited to) in the form of reading input from a file, writing output to a file.  This post describe in detail "File handling using QTP".
We use FSO object to do this.
What is FSO?
FSO stands for File System Object. This is used to support text file creation and manipulation through the TextStream object and is contained in the Scripting type library (Scrrun.dll)
The FSO Object Model has a rich set of properties, methods and events to process folders and files.
How to create a file?
We first create a FSO object using CreateObject and then create a text file using CreateTextFile.
For Example: Suppose you want to create a file called "test.txt" located in C:

Dim fso, file, file_location
file_location = "C:\file_location"
Set fso = CreateObject(“Scripting.FileSystemObject”)
Set file = fso.CreateTextFile(file_location, True) // True--> file is to be overwritten if it already exists else false

We would use the same example for the rest of this post.
How to open a file?

Set file= fso.OpenTextFile("C:\file_location", ForWriting, True)
//2nd argument can be ForReading, ForWriting, ForAppending
//3rd argument is "True" if new file has to be created if the specified file doesn’t exist else false, blank signify false.

How to read content from a file?
Use ReadLine() method
For example:

Set file= fso.OpenTextFile("C:\file_location", ForReading, True) //2nd argument should always be "ForReading" in order to read contents from a file
Do while file.AtEndofStream <> True
      data = file.ReadLine()
      msgbox data
Loop

How to write content to a file?
You can use  Write() or WriteLine() Methods to write text into a file. The difference between the Write() and WriteLine() Method is that the latter automatically inserts a new line character while the former doesn’t insert a new line character.
For example:

Set file= fso.OpenTextFile("C:\file_location", ForWriting, True) //2nd argument should always be "ForWriting" in order to write contents to a file
file.Write("This is a place to get all your qtp")
file.Write("questions and answers solved.")
//Output will be:
This is a place to get all your qtp questions and answers solved.
while
file.WriteLine("This is a place to get all your qtp")
file.Write("questions and answers solved.")
//Output will be:
This is a place to get all your qtp
questions and answers solved.

How to delete content?
Use DeleteFile() method to delete a file from a particular location
Foe Example:

file_location = "C:\file_location"
Set fso = CreateObject(“Scripting.FileSystemObject”)
fso.DeleteFile(file_location)