• 关于MVC3种IOC自写方法GetItems("Model名字")得到的Model为空的解决方法


    在项目中的PostRepository中往往会写到方法GetItems("Model") Model为关联的实例对象名称 并且这个Model还是Post的一个属性

    例如在对象Post中

    public  class Post

    {

    public int Id{get;set;}

    public int AdminId{get;set;}

    public Admin admin{get;set;}

    }

    PostRepository.GetItems("Admin")

    如果在查询的结果中出现post有值,adminId有值 但是Admin为null

    这是你可以查看一下方法GetItems

    public IQueryable<TEntity> GetItems(params Expression<Func<TEntity, object>>[] paths)
    {
    var dbSet = _dbSet as IQueryable<TEntity>;
    if (paths != null)
    foreach (var path in paths)
    dbSet = dbSet.Include(path);
    return dbSet;
    }

    dbSet返回的值:

    如果出现dbset的值为:

    {SELECT
    [Extent1].[ID] AS [ID],
    [Extent1].[CategoryID] AS [CategoryID],
    [Extent1].[AdminId] AS [AdminId],
    [Extent1].[Title] AS [Title],
    [Extent1].[Summary] AS [Summary],
    [Extent1].[Alias] AS [Alias],
    [Extent1].[Content] AS [Content],
    [Extent1].[ArticleShare] AS [ArticleShare],
    [Extent1].[ArticleVisit] AS [ArticleVisit],
    [Extent1].[ArticleReship] AS [ArticleReship],
    [Extent1].[CreateTime] AS [CreateTime],
    [Extent1].[Level] AS [Level],
    [Extent2].[AdminId] AS [AdminId1],
    [Extent2].[UserName] AS [UserName],
    [Extent2].[PassWord] AS [PassWord],
    [Extent2].[Nike] AS [Nike],
    [Extent2].[Email] AS [Email],
    [Extent2].[HeadImage] AS [HeadImage]
    FROM [dbo].[Posts] AS [Extent1]
    INNER JOIN [dbo].[Admins] AS [Extent2] ON [Extent1].[AdminId] = [Extent2].[AdminId]}

    需要注意一下红字的部分

    如果不是,出现[extent1].[admin_adminId]=[Extent2].[AdminId]

    这样的值 就是因为类:Admin中出现了 public List<Post> Posts{get;set;}

    这个属性了

    一般情况下如果是一对多的关系  

    在多种添加一的id和实体类属性就可以了

    譬如:Post中出现:AdminId 和Admin这两个属性就可以了

    不必要在
    Admin中添加List<post>属性

    嘿嘿!!! 

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  • 原文地址:https://www.cnblogs.com/douqiumiao/p/2837153.html
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