Name
CLng Function
Syntax
CLng(expression
)
expression
Use: Required
Data Type: Numeric or String
The range of
expression
is -2,147,483,648 to 2,147,483,647; fractions are rounded.
Return Value
expression
cast as a type of
Long.
Description
Converts expression
to a type of
Long; any fractional element of
expression
is rounded.
Rules at a Glance
expression
must evaluate to a numeric value; otherwise, a type mismatch error is generated.If the value of
expression
is outside the range of the long data type, an overflow error is generated.When the fractional part is exactly 0.5, CLng always rounds it to the nearest even number. For example, 0.5 rounds to 0, and 1.5 rounds to 2.
Example
<HTML> <HEAD> <SCRIPT LANGUAGE="VBScript"> Option Explicit Sub cmdAdd_OnClick( ) Dim lSum, sNum1, sNum2 sNum1 = Window.Document.frmAdd.txtText1.Value sNum2 = Window.Document.frmAdd.txtText2.Value If IsNumeric(sNum1) And IsNumeric(sNum2) Then lSum = CLng(sNum1) + CLng(sNum2) Alert "The sum is: " & lSum Else Alert "The values you enter in the text boxes must be numeric." End If End Sub </SCRIPT> </HEAD> <BODY> <FORM NAME="frmAdd"> <INPUT TYPE="text" NAME="txtText1"><BR> <INPUT TYPE="text" NAME="txtText2"><BR> <INPUT TYPE="button" NAME="cmdAdd" VALUE="Sum"> </FORM> </BODY> </HTML>
Programming Tips and Gotchas
Use IsNumeric to test whether
expression
evaluates to a number.CLng differs from the Fix and Int functions, which truncate, rather than round, the fractional part of a number. Also, Fix and Int always return a value ...
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