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File Modes

The following table lists the values you can specify for the Mode argument.

Mode Description
Append Opens the file for sequential output, beginning at the end of the file if the file exists. If the file doesn't exist, VB creates the file.
Binary In Binary mode, you can access a file at the byte level.
Input Opens the file for sequential input, starting at the beginning of the file. Data is read in the same order it was sent to the file.
Output Opens the file for sequential output, starting at the beginning of the file. If the file doesn't exist, VB creates the file; otherwise, VB overwrites the file.
Random Opens the file for random read and write access. The data can be read from or written to any specific record boundary.

Restricting Access

The optional AccessRestriction argument specifies the operations permitted on the open file: Read, Write, or Read Write.

Locking the File

Use a LockType argument value to specify the operations permitted on the open file by other processes. This parameter is useful when writing network applications. You can restrict access to a file so that only one user at a time has access to the file or can write to the file. The valid options for this argument are: Shared, Lock Read, Lock Write, and Lock Read Write.

Record Length

For files opened for random access, this value is the record length. For sequential files, this value is the number of characters buffered. This argument is necessary when accessing records from a file. The first record in a file begins at location 1, and all subsequent records are written at locations in increments of 1. The actual location in the file of any given record is N X intRecordLength, where N is the record number.

Play Sound A record is one logical line from a file that holds a complete set of data.


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