7

当我运行以下代码时，我得到一个 NullReferenceException 说对象引用未设置为对象的实例。我已经成功地插入了使用不太复杂的对象但格式相同的 dapper，所以我不确定我做错了什么。

public void Foo(IEnumerable<FogbugzCase> cases) 
{
    // using a singleton for the SqlConnection
    using (SqlConnection conn = CreateConnection())
    {
        foreach (FogbugzCase fogbugzCase in cases)
        {
            conn.Execute("INSERT INTO fogbugz.Cases(CaseId, Title, ProjectId, CategoryId, Root, MilestoneId, Priority, Status, EstimatedHours, ElapsedHours, AssignedTo, ResolvedBy, IsResolved, IsOpen, Opened, Resolved, Uri, ResolveUri, OutlineUri, SpecUri, ParentId, Backlog) VALUES(@BugId, @Title, @ProjectId, @CategoryId, @RootId, @MilestoneId, @Priority, @StatusId, @EstimatedHours, @ElapsedHours, @PersonAssignedToId, @PersonResolvedById, @IsResolved, @IsOpen, @Opened, @Resolved, @Uri, @ResolveUri, @OutlineUri, @Spec, @ParentId, @Backlog);", new {BugId = fogbugzCase.BugId, Title = fogbugzCase.Title, ProjectId = fogbugzCase.Project.Id, CategoryId = fogbugzCase.Category.Id, RootId = fogbugzCase.Root, MilestoneId = fogbugzCase.Milestone.Id, Priority = fogbugzCase.Priority, StatusId = fogbugzCase.Status.Id, EstimatedHours = fogbugzCase.EstimatedHours, ElapsedHours = fogbugzCase.ElapsedHours, PersonAssignedToId = fogbugzCase.PersonAssignedTo.Id, PersonResolvedById = fogbugzCase.PersonResolvedBy.Id, IsResolved = fogbugzCase.IsResolved, IsOpen = fogbugzCase.IsOpen, Opened = fogbugzCase.Opened, Resolved = fogbugzCase.Resolved, Uri = fogbugzCase.Uri, OutlineUri = fogbugzCase.OutlineUri, Spec = fogbugzCase.Spec, ParentId = fogbugzCase.ParentId, Backlog = fogbugzCase.Backlog});
        }
    }
}

我首先尝试使用更简单的方法来fogbugzCase代替匿名对象，但导致了关于 CategoryId 的不同异常。

有人看到我错过了什么吗？

4

1 回答 1

7

听起来其中一个属性是null. 拆分代码：

var args =  new {BugId = fogbugzCase.BugId, Title = fogbugzCase.Title, ProjectId = fogbugzCase.Project.Id, CategoryId = fogbugzCase.Category.Id, RootId = fogbugzCase.Root, MilestoneId = fogbugzCase.Milestone.Id, Priority = fogbugzCase.Priority, StatusId = fogbugzCase.Status.Id, EstimatedHours = fogbugzCase.EstimatedHours, ElapsedHours = fogbugzCase.ElapsedHours, PersonAssignedToId = fogbugzCase.PersonAssignedTo.Id, PersonResolvedById = fogbugzCase.PersonResolvedBy.Id, IsResolved = fogbugzCase.IsResolved, IsOpen = fogbugzCase.IsOpen, Opened = fogbugzCase.Opened, Resolved = fogbugzCase.Resolved, Uri = fogbugzCase.Uri, OutlineUri = fogbugzCase.OutlineUri, Spec = fogbugzCase.Spec, ParentId = fogbugzCase.ParentId, Backlog = fogbugzCase.Backlog});
conn.Execute("INSERT INTO fogbugz.Cases(CaseId, Title, ProjectId, CategoryId, Root, MilestoneId, Priority, Status, EstimatedHours, ElapsedHours, AssignedTo, ResolvedBy, IsResolved, IsOpen, Opened, Resolved, Uri, ResolveUri, OutlineUri, SpecUri, ParentId, Backlog) VALUES(@BugId, @Title, @ProjectId, @CategoryId, @RootId, @MilestoneId, @Priority, @StatusId, @EstimatedHours, @ElapsedHours, @PersonAssignedToId, @PersonResolvedById, @IsResolved, @IsOpen, @Opened, @Resolved, @Uri, @ResolveUri, @OutlineUri, @Spec, @ParentId, @Backlog);", args);

如果代码在第一行失败，它与 dapper 没有任何关系——它甚至没有接近 dapper。您需要检查所有嵌套成员。

于 2013-06-28T23:05:43.200 回答