Is there a string math evaluator in .NET?

Question

If I have a string with a valid math expression such as:

String s = \"1 + 2 * 7\";

Is there a built in library/function in .NET that will p

Answer 1

Actually there is kind of a built in one - you can use the XPath namespace! Although it requires that you reformat the string to confirm with XPath notation. I've used a method like this to handle simple expressions:

    public static double Evaluate(string expression)
    {
        var xsltExpression = 
            string.Format("number({0})", 
                new Regex(@"([\+\-\*])").Replace(expression, " ${1} ")
                                        .Replace("/", " div ")
                                        .Replace("%", " mod "));

        return (double)new XPathDocument
            (new StringReader(""))
                .CreateNavigator()
                .Evaluate(xsltExpression);
    }