How to: Write to Binary Files in Visual Basic
The WriteAllBytes method writes data to a binary file. If the append
parameter is True
, it will append the data to the file; otherwise data in the file is overwritten.
If the specified path excluding the file name is not valid, a DirectoryNotFoundException exception will be thrown. If the path is valid but the file does not exist, the file will be created.
To write to a binary file
Use the WriteAllBytes
method, supplying the file path and name and the bytes to be written. This example appends the data array CustomerData
to the file named CollectedData.dat
.
Dim CustomerData As Byte() = (From c In customerQuery).ToArray()
My.Computer.FileSystem.WriteAllBytes(
"C:\MyDocuments\CustomerData", CustomerData, True)
Robust Programming
The following conditions may create an exception:
The path is not valid for one of the following reasons: it is a zero-length string; it contains only white space; or it contains invalid characters. (ArgumentException).
The path is not valid because it is
Nothing
(ArgumentNullException).File
points to a path that does not exist (FileNotFoundException or DirectoryNotFoundException).The file is in use by another process, or an I/O error occurs (IOException).
The path exceeds the system-defined maximum length (PathTooLongException).
A file or directory name in the path contains a colon (:) or is in an invalid format (NotSupportedException).
The user lacks necessary permissions to view the path (SecurityException).