Name
CByte Function
Syntax
CByte(expression
)
expression
Use: Required
Data Type: Numeric or String
A string or numeric expression that evaluates between 0 and 255.
Return Value
expression
converted to a type of
Byte.
Description
Converts expression
to a Byte data
type. The Byte type is the smallest data storage device in VBScript.
Being only one byte in length, it can store unsigned numbers between
0 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 0 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 and Gotchas
Check that the value you pass to CByte is neither negative nor greater than 255.
Use IsNumeric to insure the value passed to CByte 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 greater than 0.5 are rounded up. Values of 0.5 are rounded to the nearest even number (i.e., they use the Banker’s Rounding Algorithm).
See Also
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