Eval Function |
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Description
Evaluates an expression and returns the result.
Syntax
Eval(expression)
Required. String containing any legal VBScript expression.
Remarks
In VBScript, x = y can be interpreted two ways. The first is as an assignment
statement, where the value of y is assigned to x. The second interpretation
is as an expression that tests if x and y have the same value. If they do, the
result is True; if they are not, the result is False. The Eval method always
uses the second interpretation, whereas the Execute statement always uses the
first.
Note In Microsoft®
JScript™, no confusion exists between assignment and comparison, because the
assignment operator (=) is different from the comparison operator (==).
The following example illustrates the use of the Eval function:
Sub GuessANumber
Dim Guess, RndNum
RndNum = Int((100) * Rnd(1) + 1)
Guess = CInt(InputBox("Enter your guess:",,0))
Do
If Eval("Guess = RndNum") Then
MsgBox "Congratulations!
You guessed it!"
Exit Sub
Else
Guess = CInt(InputBox("Sorry!
Try again.",,0))
End If
Loop Until Guess = 0
End Sub
Information: The example above will NOT work in an Active Server Pages (ASP) webpage, to see that example working you will need to make it run under Microsoft Windows Based Script Host or compile it in compatible Microsoft Visual Basic.
See Also
Execute Statement
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