Cannot use a lambda expression as an argument to a dynamically dispatched operation

Cannot use a lambda expression as an argument to a dynamically dispatched operation without first casting it to a delegate or expression tree type.

Consider the following code:

dynamic numbers = GetNumbers();

var evenNumbers = numbers.Where(n => n % 2 == 0);

foreach (var number in evenNumbers)
{
    Console.WriteLine($"Even number: {number}");
}

This results in a compilation error because numbers is dynamic, and calling .Where() with a lambda expression on a dynamic object is not directly supported.

To resolve this issue, cast the dynamic object to a known type, such as IEnumerable<dynamic>. This ensures that LINQ extension methods like .Where() can be properly resolved.

dynamic numbers = GetNumbers();

var evenNumbers = ((IEnumerable<dynamic>)numbers).Where(n => n % 2 == 0);

foreach (var number in evenNumbers)
{
    Console.WriteLine($"Even number: {number}");
}

By casting numbers to IEnumerable<dynamic>, we inform the compiler that it supports LINQ methods, allowing the lambda expression to work correctly.