Name
CLng Function
Syntax
CLng(expression
)
-
expression
Use: Required
Data Subtype: 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 Variant with a
subtype of Long.
Description
Converts expression
to a Variant with a
subtype 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 datatype, 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 & Gotchas
Use
IsNumeric
to test whetherexpression
evaluates to a number.CLng
differs from theFix
andInt
functions, which truncate, rather than round, the fractional part of a number. ...
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