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UShort data type (Visual Basic)

  • บทความ

Holds unsigned 16-bit (2-byte) integers ranging in value from 0 through 65,535.

Remarks

Use the UShort data type to contain binary data too large for Byte.

The default value of UShort is 0.

Literal assignments

You can declare and initialize a UShort variable by assigning it a decimal literal, a hexadecimal literal, an octal literal, or (starting with Visual Basic 2017) a binary literal. If the integer literal is outside the range of UShort (that is, if it is less than UInt16.MinValue or greater than UInt16.MaxValue, a compilation error occurs.

In the following example, integers equal to 65,034 that are represented as decimal, hexadecimal, and binary literals are assigned to UShort values.

Dim ushortValue1 As UShort = 65034
Console.WriteLine(ushortValue1)

Dim ushortValue2 As UShort = &HFE0A
Console.WriteLine(ushortValue2)

Dim ushortValue3 As UShort = &B1111_1110_0000_1010
Console.WriteLine(ushortValue3)
' The example displays the following output:
'          65034
'          65034
'          65034

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.

Dim ushortValue1 As UShort = 65_034
Console.WriteLine(ushortValue1)

Dim ushortValue3 As UShort = &B11111110_00001010
Console.WriteLine(ushortValue3)
' The example displays the following output:
'          65034
'          65034

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 UShort = &H_FF8C

To use the underscore character as a leading separator, you must add the following element to your Visual Basic project (*.vbproj) file:

<PropertyGroup>
  <LangVersion>15.5</LangVersion>
</PropertyGroup>

For more information see Select the Visual Basic language version.

Numeric literals can also include the US or us type character to denote the UShort data type, as the following example shows.

Dim number = &H_5826us

Programming tips

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

  • CLS Compliance. The UShort data type is not part of the Common Language Specification (CLS), so CLS-compliant code cannot consume a component that uses it.

  • Widening. The UShort data type widens to Integer, UInteger, Long, ULong, Decimal, Single, and Double. This means you can convert UShort to any of these types without encountering a System.OverflowException error.

  • Type Characters. Appending the literal type characters US to a literal forces it to the UShort data type. UShort has no identifier type character.

  • Framework Type. The corresponding type in the .NET Framework is the System.UInt16 structure.

See also