protected virtual List <Customer> ExecuteQuery <TValue>(RuleOperator op, Expression <Func <Customer, TValue> > left, object right)
{
var paramExpr = Expression.Parameter(typeof(Customer), "it");
var valueExpr = ExpressionHelper.CreateValueExpression(left.Body.Type, right); // Expression.Constant(right)
var expr = op.GetExpression(left.Body, valueExpr, true);
var predicate = ExpressionHelper.CreateLambdaExpression(paramExpr, expr);
var result = _customers.AsQueryable().Where(predicate).Cast <Customer>().ToList();
return(result);
}
public override Expression GetExpression(RuleOperator op, Expression valueExpression, bool liftToNull)
{
// Create the Any()/All() lambda predicate (the part within parentheses)
var predicate = ExpressionHelper.CreateLambdaExpression(
Expression.Parameter(typeof(TPredicate), "it2"),
op.GetExpression(PredicateExpression.Body, valueExpression, liftToNull));
var body = Expression.Call(
typeof(Enumerable),
MethodName,
// .Any/All<TPredicate>()
new[] { typeof(TPredicate) },
// 0 = left collection path: x.Orders.selectMany(o => o.OrderItems)
// 1 = right Any/All predicate: y => y.ProductId = 1
new Expression[]
{
MemberExpression.Body,
predicate
});
return(body);
}
public virtual Expression GetExpression(RuleOperator op, Expression valueExpression, bool liftToNull)
{
return(op.GetExpression(MemberExpression.Body, valueExpression, liftToNull));
}
