An expression tree is a mechanism that allows developers to create expressions that are necessary for the filters in the queries. In .NET, we have Func<T, TResult> to wrap a Where predicate and use it in multiple occurrences. We could use the same mechanism to create expression trees and leverage them in query objects.
The generic IQueryExpression interface has a provision to create an expression through Func, the following code creates contract for AsExpression().
public interface IQueryExpression<T>
{
Expression<Func<T, bool>> AsExpression();
}
The concrete expression class implements IQueryExpression with concrete methods and their interface counterpart and wraps the Where predicate inside the AsExpression method, which returns a Func object. The following code provides a wildcard...