使用linq从两个表（join）中获取数据并将结果返回到视图中

Question

I have two tables: Projects and ProjectsData and I want to execute query with join and get the result in the View.

In the Controller I have this code:

ViewBag.projectsData = (from pd in db.ProjectsData
                                   join p in db.Projects on pd.ProjectId equals p.ID
                                   where pd.UserName == this.HttpContext.User.Identity.Name 
                                   orderby p.Name, p.ProjectNo
                                   select new { ProjectData = pd, Project = p });

What I should use in the View to extract this data. I tried that:

@foreach (var item in ViewBag.projectsData)
{
    @item.pd.UserName
}

but it doesn't work...

Answer 1

In your view you are trying to access a pd property but such property doesn't exist. The property is called ProjectData .

This being said I would strongly recommend you to use view models and strongly typed views instead of ViewBag . This way you will also get Intellisense in your view which would have helped you pick the correct names.

So you could start by defining a view model that will hold all the information your view would need:

public class MyViewModel
{
    public ProjectData ProjectData { get; set; }
    public Project Project { get; set; }
}

and then inside your controller action populate this view model and pass to the view:

public ActionResult Index()
{
    var viewModel = 
        from pd in db.ProjectsData
        join p in db.Projects on pd.ProjectId equals p.ID
        where pd.UserName == this.HttpContext.User.Identity.Name 
        orderby p.Name, p.ProjectNo
        select new MyViewModel { ProjectData = pd, Project = p };
    return View(viewModel);
}

and finally inside your strongly typed view use the view model:

@model IEnumerable<AppName.Models.MyViewModel>
@foreach (var item in Model)
{
     <div>@item.ProjectData.UserName</div>
}