Vbs Tutorial: function-eval function

Eval function

Calculates the value of an expression and returns the result.

[Result =]Eval (Expression)

Parameters

Result

Optional. Is a variable used to accept the returned results. If no result is specified, consider usingExecuteStatement.

Expression

Required. It can be a string containing any valid VBScript expression.

Description

In VBScript,X = yThere are two possible interpretations. The first method is the value assignment statementYValueX. The second explanation is testXAndYEqual or not. If they are equal,ResultIsTrueOtherwiseResultIsFalse.EvalThe method always adopts the second explanation, whileExecuteThe first statement is always used.

Note:There is no confusion between this comparison and assignment in Microsoft (r) Visual Basic Scripting Edition, because the assignment operator (=) is different from the comparison operator (=.

The example below illustratesEvalFunction usage:

  sub guessanumber dim guess, 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, please try again  ", 0 ))   end if   loop until guess = 0   end sub