// C# Eval Expression

// Doc: https://eval-expression.net/register-unregister

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// @nuget: Z.Expressions.Eval

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/*

## RegisterDefaultAliasUnsafe

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The RegisterDefaultAliasUnsafe method register types , members and extension methods of some type that might be considered most unsafe such as (Console, DirectionInfo, FileInfo, etc.). You can find the complete list here:

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In this example, we will unregister all types and then register only types included in the `RegisterDefaultAliasUnsafe` methods. In fact, all types from the `RegisterDefaultAliasUnsafe` are already registered by default, but we still do it for demo purposes. First, we will create a dictionary that is part of the registered types. Then we will create a `DataTable`, but unlike when using the method `RegisterDefaultAliasSafe`, this time, the code will successfully work as the `DataTable` is part of the types registered this time.

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See more: https://eval-expression.net/register-unregister

*/

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using System;

using Z.Expressions;

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public class Program

{

    public static void Main()

    {

        // Global Context: EvalManager.DefaultContext.RegisterDefaultAliasSafe();

        var context = new EvalContext();

        context.UnregisterAll();

        context.RegisterDefaultAliasUnsafe();

        // 1 - You can access the Dictionary object since the type has been registered in the RegisterDefaultAliasSafe

        var r1 = context.Execute<int>(@"var dict = new Dictionary<string, object>(); return dict.Count;");

        Console.WriteLine("1 - Result: " + r1);

        // 1 - You can access the DataTable object with the method `RegisterDefaultAliasUnsafe` unlike the method `RegisterDefaultAliasSafe`

        var r2 = context.Execute<int>(@"var dt = new DataTable(); return dt.Rows.Count;");

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

    }

}