// C# Eval Expression

// Doc: https://eval-expression.net/options

​

// @nuget: Z.Expressions.Eval

​

/*

## UseSmartExecuteParameterResolution

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The UseSmartExecuteParameterResolution option lets you get or set if the smart resolution should be used when passing multiple values to the execute method, like the default logic, which automatically does when only one parameter is specified. This option is very similar to the option `IncludeMemberFromAllParameter` but is different in the way that we also register value to know the type already. By default, the UseSmartExecuteParameterResolution value is `false`.

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In this example, we will first try to resolve our expression with the default behavior, which will fail as you cannot use the member name directly when multiple parameters are specified. Then, we will try again, but this time, with the `UseSmartExecuteParameterResolution= true` option, which will make our expression execute successfully as we can use member names of all parameters in the expression.

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See more: https://eval-expression.net/options

*/

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using System;

using Z.Expressions;

​

public class Program

{

    public static void Main()

    {

        // Global Context: EvalManager.DefaultContext.UseSmartExecuteParameterResolution = true;

        var context = new EvalContext();

        context.UseCache = false;

        var customer = new Customer() { Name = "C# Eval Expression" };

        var invoice = new Invoice() { TotalQuantity = 13 };

​

        try

        {

            // 1 - the library include default member name when only 1 parameter is specified but not for multiples parameters

            var fail = context.Execute("return $'the customer {customer.Name} ordered {invoice.TotalQuantity} items';", new { customer }, new { invoice});

        }

        catch(Exception ex)

        {       

            Console.WriteLine("1 - Exception: " + ex.Message);

        }

        // 2 - however, you can have the behavior to include members of all parameters with the option `UseSmartExecuteParameterResolution`

        context.UseSmartExecuteParameterResolution = true;

        var r2 = context.Execute("return $'the customer {customer.Name} ordered {invoice.TotalQuantity} items';", new { customer }, new { invoice});

        Console.WriteLine("2 - Result: " + r2);

    }

    public class Customer

    {

        public string Name { get; set; }

    }

    public class Invoice

    {

        public int TotalQuantity { get; set; }

    }

}