I currently have an ASP.NET Core 2.0 Web Application (built in VS 2017 from the default web application template). I have a RazorPage with a dropdown built in that I would like to populate via a SQL Query. I've used Entity Framework Core to build a model of my database as follows:
public partial class INVOPEContext : DbContext
{
public virtual DbSet<PmeFundData> PmeFundData { get; set; }
modelBuilder.HasAnnotation"Relational:DefaultSchema", "Server\\User");
modelBuilder.Entity<PmeFundData>(entity =>
{
entity.ToTable("PME_FUND_DATA", "dbo");
entity.Property(e => e.Firm).HasMaxLength(255);
});
}
public partial class PmeFundData
{
public string Firm { get; set; }
}
I've updated the RazorPage PageModel (pmepe.cshtml.cs) to include the DBContext and Query:
public class pmepeModel : PageModel
{
private readonly INVOPEContext _db;
public pmepeModel(INVOPEContext db)
{
_db = db;
}
public IActionResult dropdowns()
{
List<PmeFundData> firmList = new List<PmeFundData>();
firmList = (from Firm in _db.PmeFundData
select Firm).Distinct().ToList();
firmList.Insert(0, new PmeFundData {Firm = "All Firms" });
ViewBag.ListofFirms = firmList;
return View();
}
}
Finally, the view with the dropdown (pmepe.cshtml) is as follows:
@page
@model pmepeModel
@{
ViewData["Title"] = "pmepe";
}
<select asp-for="dropdowns"
id="firm"
class="dropdown"
asp-items= "@(new SelectList(ViewBag.ListofFirms, "Firm"))">
</select>
I am getting errors that neither ViewBag nor View exist in the current context in the PageModel (no errors in the view - Intellisense picks it up). Every example I've found on the web is for MVC rather than RazorPages. The solution commonly provided for MVC is imbedding the query in a Controller and adjusting the MVC version in the web.config file. But the RazorPages template doesn't have Controllers and I can't find a web.config file - so I haven't been able to get it to work in my app. Any help you can provide would be most appreciated.
There are multiple issues in your code.
PmeFundData
should have Id
property, otherwise, you will receive error while running update-database
command.
public partial class PmeFundData
{
public int Id { get; set; }
public string Firm { get; set; }
}
ViewBag
is not supported in RazorPage, you could trace this issue from Add ViewBag to PageModel #6754, you could try ViewData
or PageModel Property
to bind the object.
Here is a simple code for ViewData
.
public class PmepeModelModel : PageModel
{
private readonly CoreRazor2_1.Data.ApplicationDbContext _context;
public PmepeModelModel(CoreRazor2_1.Data.ApplicationDbContext context)
{
_context = context;
}
public IActionResult OnGet()
{
return Page();
}
[BindProperty]
public int SelectedFirm { get; set; }
[ViewData]
public IList<PmeFundData> ListofFirms { get {
return Dropdowns();
}
}
public IList<PmeFundData> Dropdowns()
{
List<PmeFundData> firmList = new List<PmeFundData>();
firmList = new List<PmeFundData> {
new PmeFundData{ Id = 1, Firm = "F1"},
new PmeFundData{ Id = 2, Firm = "F3"},
new PmeFundData{ Id = 3, Firm = "F2"}
};
//firmList = (from Firm in _context.PmeFundData
// select Firm).Distinct().ToList();
firmList.Insert(0, new PmeFundData { Firm = "All Firms" });
return firmList;
//ViewData["ListofFirms"] = firmList;
}
public async Task<IActionResult> OnPostAsync()
{
var value = SelectedFirm;
if (!ModelState.IsValid)
{
return Page();
}
_context.PmeFundData.Add(PmeFundData);
await _context.SaveChangesAsync();
return RedirectToPage("./Index");
}
}
View
@page
@model CoreRazor2_1.Pages.PmepeModelModel
@{
ViewData["Title"] = "PmepeModel";
}
<h2>PmepeModel</h2>
<h4>PmeFundData</h4>
<hr />
<div class="row">
<div class="col-md-4">
<form method="post">
<select asp-for="@Model.SelectedFirm"
class="dropdown"
asp-items="@(new SelectList((IEnumerable<PmeFundData>)@ViewData["ListofFirms"], "Id" ,"Firm"))">
</select>
<div class="form-group">
<input type="submit" value="Create" class="btn btn-default" />
</div>
</form>
</div>
</div>
<div>
<a asp-page="Index">Back to List</a>
</div>
@section Scripts {
@{await Html.RenderPartialAsync("_ValidationScriptsPartial");}
}
You may also learn Razor Page
from Introduction to Razor Pages in ASP.NET Core