FileSystem.ReadAllBytes(String) Method

Definition

Returns the contents of a file as a byte array.

C#
public static byte[] ReadAllBytes(string file);

Parameters

file
String

File to be read.

Returns

Byte[]

Byte array containing the contents of the file.

Exceptions

The path is not valid for one of the following reasons: it is a zero-length string; it contains only white space; it contains invalid characters; or it is a device path (starts with \.\); it ends with a trailing slash.

file is Nothing.

The file does not exist.

The file is in use by another process, or an I/O error occurs.

The path exceeds the system-defined maximum length.

A file or directory name in the path contains a colon (:) or is in an invalid format.

There is not enough memory to write the string to buffer.

The user lacks necessary permissions to view the path.

Examples

This example reads from the file C:/Documents and Settings/selfportrait.jpg.

VB
My.Computer.FileSystem.ReadAllBytes(
  "C:/Documents and Settings/selfportrait.jpg")

Remarks

The ReadAllBytes method of the My.Computer.FileSystem object allows you to read from a binary file. The contents of the file are returned as a byte array.

Do not make decisions about the contents of the file based on the name of the file. For example, the file Form1.vb may not be a Visual Basic source file. Verify all inputs before using the data in your application.

The following table lists an example of a task involving the My.Computer.FileSystem.ReadAllBytes method.

To See
Read from a binary file How to: Read From Binary Files in Visual Basic

Applies to

Product Versions
.NET Core 3.0, Core 3.1, 5, 6, 7, 8, 9
.NET Framework 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1