protected override Expression VisitMethodCall(MethodCallExpression exp)
{
var method = exp.Method;
_isAny = method.Name == LinqConsts.EnumerableMethod_Any;
//先访问表达式 book.ChapterList.Cast<Chapter>()，获取列表属性。
var invoker = exp.Arguments[0];
_parentPropertyFinder.Find(invoker);
var listPropertyTable = _parentPropertyFinder.PropertyOwnerTable;
var listProperty = _parentPropertyFinder.Property as IListProperty;
if (listProperty == null)
{
throw EntityQueryBuilder.OperationNotSupported(invoker);
}
//为该列表对应的实体创建表对象、查询对象。
var childRepo = RepositoryFactoryHost.Factory.FindByEntity(listProperty.ListEntityType);
var childTable = f.Table(childRepo);
_query = f.Query(
from: childTable,
selection: f.Literal("1")
);
var qgc = QueryGenerationContext.Get(_parentQuery);
qgc.Bind(_query);
childTable.Alias = qgc.NextTableAlias();
//Any、All 方法如果有第二个参数，那么第二个参数就是条件表达式。如：c => c.Name == chapterName
if (exp.Arguments.Count == 2)
{
var reverseWhere = !_isAny;//如果是 All，则需要反转里面的所有操作符。
var queryBuilder = new EntityQueryBuilder(childRepo, reverseWhere);
queryBuilder.BuildQuery(exp.Arguments[1], _query);
}
//添加子表查询与父实体的关系条件：WHERE c.BookId = b.Id
var parentProperty = childRepo.FindParentPropertyInfo(true);
var parentRefIdProperty = (parentProperty.ManagedProperty as IRefProperty).RefIdProperty;
var toParentConstraint = f.Constraint(childTable.Column(parentRefIdProperty), listPropertyTable.IdColumn);
_query.Where = f.And(toParentConstraint, _query.Where);
return(exp);
}
