[2.0] Changing from int to double?

[Fromethius]

Well.. I am basically doing math functions and I got this from my good ol' friend, Coniptoer

        /// <summary>
        /// A simple function to get the result of a C# expression (basic and advanced math possible)
        /// </summary>
        /// <param name="command">String value containing an expression that can evaluate to a double.</param>
        /// <returns>a Double value after evaluating the command string.</returns>
        private double ProcessCommand(string command)
        {
            //Create a C# Code Provider
            CSharpCodeProvider myCodeProvider = new CSharpCodeProvider();
            // Build the parameters for source compilation.
            CompilerParameters cp = new CompilerParameters();
            cp.GenerateExecutable = false;//No need to make an EXE file here.
            cp.GenerateInMemory = true;   //But we do need one in memory.
            cp.OutputAssembly = "TempModule"; //This is not necessary, however, if used repeatedly, causes the CLR to not need to 
            //load a new assembly each time the function is run.
            //The below string is basically the shell of a C# program, that does nothing, but contains an
            //Evaluate() method for our purposes.  I realize this leaves the app open to injection attacks, 
            //But this is a simple demonstration.
            string TempModuleSource = "namespace ns{" +
                                      "using System;" +
                                      "class class1{" +
                                      "public static double Evaluate(){return " + command + ";}}} ";  //Our actual Expression evaluator

            CompilerResults cr = myCodeProvider.CompileAssemblyFromSource(cp, TempModuleSource);
            if (cr.Errors.Count > 0)
            {
                //If a compiler error is generated, we will throw an exception because 
                //the syntax was wrong - again, this is left up to the implementer to verify syntax before
                //calling the function.  The calling code could trap this in a try loop, and notify a user 
                //the command was not understood, for example.
                throw new ArgumentException("Expression cannot be evaluated, please use a valid C# expression");
            }
            else
            {
                MethodInfo Methinfo = cr.CompiledAssembly.GetType("ns.class1").GetMethod("Evaluate");
                return (double)Methinfo.Invoke(null, null);
            }
        }

However, it appears that when dividing, it is using integers. If I put 26 / 3 in my program instead of getting 8.67, I get 8. Let's do 25 / 3. We get 8.3333 etc.. However, in my program I am still getting 8 in both cases. Anyone know how to fix this? I want decimals

[conipto]

Since that is essentially just passing a string to the C# program contained in the TempModuleSource, you would have to do the same thing that any C# program would do when working with literals. That is, 25.0 / 8.0 will give you your decimal result. the only way around this and to always assume a decimal literal would probably be to parse the string before sending it and add the .0 when necessary. Easier said than done, however..

Bill

[Fromethius]

OT:

Hey Conipto, why aren't you on aim or msn?