c# - NHibernate.QueryException 消息 : duplicate association path

Question

我有这个代码:

if (pertinentDataExists) {        
    List<Entity> operatorList = new List<Operator>();
    List<Entity> newOperatorList = criteria.newOperatorList;
    foreach (Operator operator in operatorList)
    {
        operatorList.Add(operator);
    }
    queryCriteria.CreateCriteria("OperatorList").Add(Restrictions.In("Operator", operatorList));
}

然后是:

if (otherPertinentDataExists) {
    Object[] objects = new Object[criteria.newRoleTypeList.Count];                                                                                                                
    for (int  = 0; i < criteria.RoleTypeList.Count; i++) {                                                                                       
        objects[i] = criteria.RoleTypeList[i].Id;   
    }                                                                                       
    queryCriteria.CreateCriteria("OperatorList").Add(Restrictions.In("Role", objects));
}

这些单独工作就好了。但是，如果这两种情况都有要添加到列表中的标准，那么我会得到:

NHibernate.QueryException Message : duplicate association path: OperatorList

如果条件已创建，我如何为 Role 添加限制？

Answer 1

有两种选择。首先，如果可能(在同一方法中)，创建 Criteria 并将它们作为局部变量引用:

var operatorListCriteria = queryCriteria.CreateCriteria("OperatorList");

if ( myCondition1 )
{
  operatorListCriteria.Add(...
}
if ( myCondition2 )
{
  operatorListCriteria.Add(...
}

第二步，使用“别名”创建条件，之后，您可以在任何地方使用 GetCriteriaByAlias(aliasPath) 找到它们:

var aliasPath = "OperatorListAlias";
var operatorListCriteria = queryCriteria.CreateCriteria("OperatorList", aliasPath);
...
// later find them by aliasPath
var subCriteria = queryCriteria.GetCriteriaByAlias(aliasPath);

注意:同时检查 GetCriteriaByPath(associationPath)