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Learn more about: Byte data type (Visual Basic)
Byte Data Type
01/31/2018
vb.Byte
Byte data type
data types [Visual Basic], assigning
eed44dff-eaee-4937-a89f-444e418e74f6

Byte data type (Visual Basic)

Holds unsigned 8-bit (1-byte) integers that range in value from 0 through 255.

Remarks

Use the Byte data type to contain binary data.

The default value of Byte is 0.

Literal assignments

You can declare and initialize a Byte variable by assigning it a decimal literal, a hexadecimal literal, an octal literal, or (starting with Visual Basic 2017) a binary literal. If the integral literal is outside the range of a Byte (that is, if it is less than xref:System.Byte.MinValue?displayProperty=nameWithType or greater than xref:System.Byte.MaxValue?displayProperty=nameWithType), a compilation error occurs.

In the following example, integers equal to 201 that are represented as decimal, hexadecimal, and binary literals are implicitly converted from Integer to byte values.

[!code-vbByte]

Note

You use the prefix &h or &H to denote a hexadecimal literal, the prefix &b or &B to denote a binary literal, and the prefix &o or &O to denote an octal literal. Decimal literals have no prefix.

Starting with Visual Basic 2017, you can also use the underscore character, _, as a digit separator to enhance readability, as the following example shows.

[!code-vbByte]

Starting with Visual Basic 15.5, you can also use the underscore character (_) as a leading separator between the prefix and the hexadecimal, binary, or octal digits. For example:

Dim number As Byte = &H_6A

[!INCLUDE supporting-underscores]

Programming tips

  • Negative Numbers. Because Byte is an unsigned type, it cannot represent a negative number. If you use the unary minus (-) operator on an expression that evaluates to type Byte, Visual Basic converts the expression to Short first.

  • Format Conversions. When Visual Basic reads or writes files, or when it calls DLLs, methods, and properties, it can automatically convert between data formats. Binary data stored in Byte variables and arrays is preserved during such format conversions. You should not use a String variable for binary data, because its contents can be corrupted during conversion between ANSI and Unicode formats.

  • Widening. The Byte data type widens to Short, UShort, Integer, UInteger, Long, ULong, Decimal, Single, or Double. This means you can convert Byte to any of these types without encountering a xref:System.OverflowException?displayProperty=nameWithType error.

  • Type Characters. Byte has no literal type character or identifier type character.

  • Framework Type. The corresponding type in the .NET Framework is the xref:System.Byte?displayProperty=nameWithType structure.

Example

In the following example, b is a Byte variable. The statements demonstrate the range of the variable and the application of bit-shift operators to it.

[!code-vbVbVbalrDataTypes#16]

See also