Name
CByte Function
Syntax
CByte(expression
)
-
expression
Use: Required
Data Subtype: Numeric or String
A string or numeric expression that evaluates between 0 and 255.
Return Value
expression
converted to a variant with a
subtype of Byte.
Description
Converts expression
to a Variant with a
subtype of Byte. The byte subtype is the smallest data storage device
in VBScript. Being only one byte in length, it can store unsigned
numbers between
and 255.
Rules at a Glance
If
expression
is a string, the string must be capable of being treated as a number.If
expression
evaluates to less than or more than 255, an overflow error is generated.If
expression
isn’t a whole number,CByte
rounds the number prior to conversion.
Example
If IsNumeric(sMyNumber) Then If val(sMyNumber) >= 0 and val(sMyNumber) <= 255 Then BytMyNumber = Cbyte(sMyNumber) End If End If
Programming Tips & Gotchas
Check that the value you pass to
CByte
is neither negative nor greater than 255.Use
IsNumeric
to insure the value passed toCByte
can be converted to a numeric expression.When using
CByte
to convert floating point numbers, fractional values up to but not including 0.5 are rounded down, while values of 0.5 and above are rounded up.
See Also
IsNumeric Function |
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