// C# Extension Method

// Doc: https://csharp-extension.com/en/method/1002521/object-tonullableint64ordefault

​

// @nuget: Z.ExtensionMethods

​

using System;

public class Program

{

    public static void Main()

    {

        object val1 = 123;

        object val2 = "10986423210";

        object thisNull = null;

        object thisInvalid = "A100";

        string format = "{0, -20} {1, -15}";

        Console.WriteLine(format, "Object", "ToNullableInt64OrDefault");

        Console.WriteLine(format, "------", "------------------------");

        // C# Extension Method: Object - ToNullableInt64OrDefault

        Console.WriteLine(format, val1, val1.ToNullableInt64OrDefault());

        Console.WriteLine(format, val2, val2.ToNullableInt64OrDefault());

        Console.WriteLine(format, "null", thisNull.ToNullableInt64OrDefault());

        Console.WriteLine(format, thisInvalid, thisInvalid.ToNullableInt64OrDefault());

        Console.WriteLine(format, thisInvalid, thisInvalid.ToNullableInt64OrDefault(-1));

        Console.WriteLine(format, thisInvalid, thisInvalid.ToNullableInt64OrDefault(() => -2));

    }

}