ASP.NET MVC Partial View基本使用

Model:

    public class TestModel
    {
        [Required]
        public string Id { get; set; }
    }

Partial View(PartialInput.cshtml):

@model partialview.Models.TestModel

@using (@Html.BeginForm("Index", "Test", FormMethod.Post, new { @id = "form1", @enctype = "multipart/form-data" }))
{
    

        @*使用ViewData传递数据*@
        
@ViewData["Name"]

        @Html.TextBoxFor(model => model.Id)
        "submit" id="btn" value="Submit">
    

}

Index View(Index.cshtml):

@{
    ViewBag.Title = "Index";
}


    @{
        Html.RenderPartial("PartialInput");
    }

Read data from DB in Controller:

    public class TestController : Controller
    {
        // GET: Test
        public ActionResult Index()
        {
            ViewData["Name"] = GetValue(2);
            return View();
        }

        [HttpPost]
        public ActionResult Index(TestModel model)
        {
            ViewData["Name"] = GetValue(Convert.ToInt32(model.Id));
            return View();
        }

        public string GetValue(int id)
        {
            string connSQL = @"Data Source=(localdb)\ProjectsV13;Initial Catalog=master;Integrated Security=True;Connect Timeout=30;Encrypt=False;TrustServerCertificate=False;ApplicationIntent=ReadWrite;MultiSubnetFailover=False";

            using (SqlConnection conn = new SqlConnection(connSQL))
            {
                string strSQL = "select name from PartialTest where id = " + id.ToString();
                SqlCommand cmd = new SqlCommand(strSQL, conn);

                conn.Open();
                if (cmd.ExecuteScalar() == null)
                {
                    return "NULL";
                }
                else
                {
                    return cmd.ExecuteScalar().ToString();
                }
            }
        }
    }