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FreeFile Function 

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Returns an Integer value representing the next file number available for use by the FileOpen function.

Public Function FreeFile() As Integer

Exceptions

Exception type Error number Condition

IOException

67

More than 255 files are in use.

See the "Error number" column if you are upgrading Visual Basic 6.0 applications that use unstructured error handling. (You can compare the error number against the Number Property (Err Object).) However, when possible, you should consider replacing such error control with Structured Exception Handling Overview for Visual Basic.

Remarks

Use FreeFile to supply a file number that is not already in use.

Example

This example uses the FreeFile function to return the next available file number. Five files are opened for output within the loop, and some sample data is written to each.

Dim count As Integer
Dim fileNumber As Integer
For count = 1 To 5   
   fileNumber = FreeFile()
   FileOpen(fileNumber, "TEST" & count & ".TXT", OpenMode.Output)
   PrintLine(fileNumber, "This is a sample.")
   FileClose(fileNumber)
Next

Smart Device Developer Notes

This function is not supported.

Requirements

Namespace: Microsoft.VisualBasic

Module: FileSystem

Assembly: Visual Basic Runtime Library (in Microsoft.VisualBasic.dll)

See Also

Reference

FileOpen Function
IOException Class

Other Resources

Writing to Files in Visual Basic