// C# Eval Expression

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

​

// @nuget: Z.Expressions.Eval

​

/*

## RetryAndThrowMissingTypes

​

The RetryAndThrowMissingTypes option lets you get or set if an error should be thrown by trying again to compile the expression and populate the `MissingTypes` list with types missing to make an expression valid. To compile an expression by automatically adding missing types, use the `AutoAddMissingTypes` option instead. By default, the RetryAndThrowMissingTypes is `false`.

​

In this example, we will set the `RetryAndThrowMissingTypes = true;` option and try to evaluate an expression. First, we will see that an exception is thrown with the message containing all missing types, and then we will show them again through the `MissingTypes` option.

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

*/

​

using System;

using System.Collections.Generic;

using Z.Expressions;

​

public class Program

{

    public static void Main()

    {

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

​

        var context = new EvalContext();

        context.RetryAndThrowMissingTypes = true;

        try

        {

            var entity = (Entity)context.Execute("return new Entity() { EntityID = 13 }");

        }

        catch(Exception ex)

        {

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

​

            foreach(var missingType in context.MissingTypes)

            {

                Console.WriteLine("2 - Missing Types: " + missingType.FullName);

            }

        }

    }

    public class Entity

    {

        public int EntityID { get; set; }

    }

}

​

​