How to display value by selecting from model in the controller ASP MVC-CodePudding

I want to display a name in the razor page by select it from a model and pass it through Viewbag in the controller.

Controller

public IActionResult sheet()
    {
        var tp1 = _db.Topic.Where(t => t.sheet_id == 1).ToList();
        var tp1name = tp1.Select(t => t.topic1name);
        ViewBag.tp1name = tp1name;
        return View();
    }

Model

public class Topic
{
    [Key]
    public int topic_id { get; set; }
    [Required]
    public int sheet_id { get; set; }
    [Required]
    public string topic1name { get; set; }
    [Required]
    public string topic2name { get; set; }
}
public class Transaction
{
    [Key]
    public int id { get; set; }
    [Required]
    public int sheet_id { get; set; }
    [Required]
    public string topic1score { get; set; }
}

View page

@model transaction
<table >
 <tr>
    <td rowspan="2">1</td>
    <td rowspan="2">@ViewBag.tp1name</td>
    <td rowspan="2">30</td>
    <td>Below average</td>
    <td>Average</td>
    <td>Above average</td>
  </tr>

It returns System.Linq.Enumerable SelectListIterator`2[UserLoginApp.Models.Topic,System.String] in the view page instead of topic1name

CodePudding user response：

tp1 is a list of topics.
so when you do a select it creates a new Enumerable en for each item in tp1 it selects the value of topic1name.

Thus creating an Enumerable SelectListIterator

I think you want the value of one item:

    var tp1 = _db.Topic.FirstOrDefault(t => t.sheet_id == 1)
    if(tp1 != null)
         ViewBag.tp1name = tp1.topic1name;