// C# Eval Expression

// Doc: https://eval-expression.net/my-first-evaluation

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// @nuget: Z.Expressions.Eval

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/*

## Use Option to Add Method

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In the C# Eval Expression library, it's possible to add your own method. If you can create the method in a non-dynamic way, you should always prefer this method and [register your method](/register-unregister) over creating a method dynamically.

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In this example, we will create a method dynamically that is supposed to compare three numbers and use the formula from user input to determine if they are equal or not.

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See more: https://eval-expression.net/my-first-evaluation

*/

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using System;

using System.Collections.Generic;

using Z.Expressions;

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public class Program

{

    public static void Main()

    {

        string userInputFormula = "A == B || A == -1 || B == -1";

        var evalContext = new EvalContext();

        evalContext.UseCache = false;       

        evalContext.AddMethod($$"""public bool IsEqualsCustom(int A, int B) { return {{userInputFormula}}; }""");

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        Console.WriteLine(evalContext.Execute<bool>("IsEqualsCustom(1, 1)")); 

        Console.WriteLine(evalContext.Execute<bool>("IsEqualsCustom(1, 2)")); 

        Console.WriteLine(evalContext.Execute<bool>("IsEqualsCustom(1, -1)")); 

    }

}