Browse DevX
Sign up for e-mail newsletters from DevX

Tip of the Day
Language: Visual Basic
Expertise: Intermediate
Feb 24, 2000



Building the Right Environment to Support AI, Machine Learning and Deep Learning

Wrap I/O for Text Files

In a production application, every time you want to access a file for reading or writing, you must retrieve a free handle using the FreeFile() function to ensure you don't overwrite an existing handle. You also must remember to close the file after you finish with it. In some cases, you can avoid the trouble by encasing this functionality inside utility functions. For example, I wrote these two functions to go between strings and text files in my apps:
Public Function ReadFile(FileName As String) As String
	Dim hFile As Integer
	hFile = FreeFile
	On Error GoTo ErrorTrap
		Open FileName For Input As #hFile
		ReadFile = Input(LOF(hFile), hFile)
		Close # hFile
	Exit Function
	ReadFile = ""
End Function
Public Sub WriteFile(FileName As String, Contents As 	_
	Dim hFile As Integer
	hFile = FreeFile
	On Error Resume Next
	Open FileName For Output As #hFile
	Print #hFile, Contents;
	Close #hFile
End Sub
Once you put these functions in your project, you can read and write text files quickly. For example, here's a way you might use these functions to copy text files:
Call WriteFile("c:\b.txt", ReadFile("c:\a.txt"))
Konstantin Komissarchik
Comment and Contribute






(Maximum characters: 1200). You have 1200 characters left.



Thanks for your registration, follow us on our social networks to keep up-to-date