Name
CByte Function
Named Arguments
No
Syntax
CByte(expression
)
-
expression
Use: Required
Data Type: Numeric or String
A string or numeric expression that evaluates to a number between 0 and 255
Return Value
expression
converted to Byte data type
Description
Converts expression
to a Byte data type
Rules at a Glance
If the expression to be converted is a string, the string must be capable of conversion to a numeric expression; this can be checked using the
IsNumeric
function.If
expression
evaluates to less than 0 or more than 255, a runtime error is generated.If the value of
expression
is not 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 ensure that 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 .5 are rounded down, while values above but not including .5 are rounded up. Values whose fractional component is exactly equal to .5 are rounded up if their integral component is odd and down if their integral component is even.The
CByte
function converts an expression to an unsigned byte data type. To convertexpression
to a signed byte data type, create an instance of the SByte class and call its Parse method. ...
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