How to use Seek function in VBA?

In VBA, the `Seek` function is used to find out the current position of the file pointer in an open file or to set the position for the next read/write operation within a file opened using the `Open` statement in binary mode.

Here’s how to use the `Seek` function:

Open a file using the `Open` statement with Binary, Input, or Output mode.
Use `Seek` to either retrieve or set the position of the file pointer.

To get the current position:

Dim fileNumber As Integer
Dim currentPosition As Long

fileNumber = FreeFile() ' Get the next available file number
Open "C:pathtoyourfile.txt" For Binary Access Read As #fileNumber
currentPosition = Seek(fileNumber) ' Retrieve the current position
Close #fileNumber

To set a new position:

Dim fileNumber As Integer
Dim newPosition As Long

fileNumber = FreeFile() ' Get the next available file number
Open "C:pathtoyourfile.txt" For Binary Access Write As #fileNumber

newPosition = 100 ' Example of the new position you want to set
Seek #fileNumber, newPosition ' Set the new position

' Now you can read from or write to the file at the new position
' ...

Close #fileNumber

Please note the following:

When using `Seek` to set a new position, if you specify a position beyond the current end-of-file, the file size is increased to accommodate the new position and the intervening bytes are filled with zeros.
When you use `Seek` in conjunction with files opened for `Binary` access, you can move to any position within the file and read or write bytes from that position.
When you use `Seek` with files opened for `Input` or `Output`, you are dealing with records rather than arbitrary byte positions.

It’s important to handle errors when dealing with file operations, so consider using `On Error` statements to catch any unexpected problems, and always ensure you close files after you’re done with them to avoid locking the file or leaking system resources.

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