C#•3w ago

✅ the type or namespace name 'ListingProjects' does not exist in the namespace models

So I don't understand why my code has been getting this message. It started when I added a new attribute to my model class in my CRUD app like this

public class ListingProjects_ver2 //I renamed the model class name as well 
{
    
    [System.ComponentModel.DataAnnotations.Key]
    [Required]
    public int? Id { get; set; } // Primary key for DTO
    
    [Required]
    public string? ListingName { get; set; } 

    [Required]
    [NotMapped]
    public IFormFile? ListingImage { get; set; } //this is the attribute I added 
}

public class ListingProjects_ver2 //I renamed the model class name as well 
{
    
    [System.ComponentModel.DataAnnotations.Key]
    [Required]
    public int? Id { get; set; } // Primary key for DTO
    
    [Required]
    public string? ListingName { get; set; } 

    [Required]
    [NotMapped]
    public IFormFile? ListingImage { get; set; } //this is the attribute I added 
}

My CRUD lets me create/delete/read my data out of my db, but only the edit operation fails. It does not save my edits as per screenshot My debug shows this message the type or namespace name 'ListingProjects' does not exist in the namespace models (are you missing a reference) Could anyone kindly point me in the direction to resolve this bug?

21 Replies

TheRanger•3w ago

where in ur code are u exactly getting this message

jcotton42•3w ago

The error message complains about ListingProjects but your class is named ListingProjects_ver2 @morry329#.

morry329#OP•3w ago

oops I forgot to post the pastebin link where the whole code is https://pastebin.com/Fj82WLN2 My code is getting that message here

    public async Task<JsonResult> EditListingJpost([FromForm] int Id, [FromForm] string ListingName, [FromForm] IFormFile ListingImage)
    {
 
        var listingToUpdate = await _context.ListingVer2_DBTable.FirstOrDefaultAsync(s => s.Id == Id); 
 
        if (listingToUpdate == null) //not null, so this check was passed 
        {
            return Json(new { success = false, message = "Listing not found." });
        }
 
        /* my problem lies here - the await check was not passed which means my change was not saved into DB */
        if (await TryUpdateModelAsync<ListingProjects_ver2>(listingToUpdate, "", s => s.ListingName))
        {
            try
            {
 
                await _context.SaveChangesAsync();
                return Json(new { success = true, updatedListing = listingToUpdate });
            }
            catch (DbUpdateException)
            {
                return Json(new { success = false, message = "Unable to save changes." });
            }
        }
        /* as my change was not saved via await above, the debug directly went this return. the error (the type or namespace name 'ListingProjects' does not exist in the namespace models (are you missing a reference)) points here */ 
        return Json(listingToUpdate);
    }

    public async Task<JsonResult> EditListingJpost([FromForm] int Id, [FromForm] string ListingName, [FromForm] IFormFile ListingImage)
    {
 
        var listingToUpdate = await _context.ListingVer2_DBTable.FirstOrDefaultAsync(s => s.Id == Id); 
 
        if (listingToUpdate == null) //not null, so this check was passed 
        {
            return Json(new { success = false, message = "Listing not found." });
        }
 
        /* my problem lies here - the await check was not passed which means my change was not saved into DB */
        if (await TryUpdateModelAsync<ListingProjects_ver2>(listingToUpdate, "", s => s.ListingName))
        {
            try
            {
 
                await _context.SaveChangesAsync();
                return Json(new { success = true, updatedListing = listingToUpdate });
            }
            catch (DbUpdateException)
            {
                return Json(new { success = false, message = "Unable to save changes." });
            }
        }
        /* as my change was not saved via await above, the debug directly went this return. the error (the type or namespace name 'ListingProjects' does not exist in the namespace models (are you missing a reference)) points here */ 
        return Json(listingToUpdate);
    }

` The return got that error

Pastebin

[HttpPost] public async Task EditListingJpost([FromForm] int Id ...

Pastebin.com is the number one paste tool since 2002. Pastebin is a website where you can store text online for a set period of time.

TheRanger•3w ago

is your ListingProjects_ver2 in a namespace? and did you put using that namespace in where ur trying to reference the class?

morry329#OP•3w ago

I found it strange that the error complains about ListingProjects --- my class is named ListingProjects_ver2 and it has no reference to ListingProjects. Any clue? This is my whole code https://pastebin.com/Fj82WLN2

Pastebin

[HttpPost] public async Task EditListingJpost([FromForm] int Id ...

Pastebin.com is the number one paste tool since 2002. Pastebin is a website where you can store text online for a set period of time.

TheRanger•3w ago

odd, i dont see ListingProjects anywhere can u show the error message? it should point out which file and which line is the error coming from

morry329#OP•3w ago

using System.Diagnostics;
using System.Text.Json;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using WebApplication1.Data;
using WebApplication1.Models;
using JsonException = Newtonsoft.Json.JsonException;

namespace WebApplication1.Controllers; //no, I did not put the ListingProject here

public class HomeController : Controller
{
    
    private readonly ApplicationDbContext _context;
    private ListingProjects_ver2 _listingProjectsDto;
    
/* all the other codes ... */

using System.Diagnostics;
using System.Text.Json;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using WebApplication1.Data;
using WebApplication1.Models;
using JsonException = Newtonsoft.Json.JsonException;

namespace WebApplication1.Controllers; //no, I did not put the ListingProject here

public class HomeController : Controller
{
    
    private readonly ApplicationDbContext _context;
    private ListingProjects_ver2 _listingProjectsDto;
    
/* all the other codes ... */

` So this is the snippet where this error popped in (in the controller class) . ListingProjects_ver2 is not in a namespace Please give me some minutes I have to replicate the error

morry329#OP•3w ago

So this is where the error message came from (please see the attached mp4) When I read InternalDbSet I can only think of that error coming from

namespace WebApplication1.Data;

public class ApplicationDbContext : IdentityDbContext<PortalUsers>
{
    public ApplicationDbContext(){}
    public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options)
        : base(options)
    {
    }

    public Microsoft.EntityFrameworkCore.DbSet<PortalUsers> UsersDBTable { get; set; }
    //public Microsoft.EntityFrameworkCore.DbSet<Category> CategoriesDBTable { get; set; }
    public Microsoft.EntityFrameworkCore.DbSet<ListingProjects> ListingDBTable { get; set; }
    //public Microsoft.EntityFrameworkCore.DbSet<Location> LocationDBTable { get; set; }
    public Microsoft.EntityFrameworkCore.DbSet<ListingProjects_ver2> ListingVer2_DBTable { get; set; }
    public Microsoft.EntityFrameworkCore.DbSet<ListingDtoEditClass> ListingDtoEdit_DBTable { get; set; }
    
    
}

namespace WebApplication1.Data;

public class ApplicationDbContext : IdentityDbContext<PortalUsers>
{
    public ApplicationDbContext(){}
    public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options)
        : base(options)
    {
    }

    public Microsoft.EntityFrameworkCore.DbSet<PortalUsers> UsersDBTable { get; set; }
    //public Microsoft.EntityFrameworkCore.DbSet<Category> CategoriesDBTable { get; set; }
    public Microsoft.EntityFrameworkCore.DbSet<ListingProjects> ListingDBTable { get; set; }
    //public Microsoft.EntityFrameworkCore.DbSet<Location> LocationDBTable { get; set; }
    public Microsoft.EntityFrameworkCore.DbSet<ListingProjects_ver2> ListingVer2_DBTable { get; set; }
    public Microsoft.EntityFrameworkCore.DbSet<ListingDtoEditClass> ListingDtoEdit_DBTable { get; set; }
    
    
}

` This DB class -- it does have a DB table with ListingProject type, but not sure why it could be the culprit to this error

TheRanger•3w ago

do u even have a class called ListingProjects defined?

morry329#OP•3w ago

yes

TheRanger•3w ago

where?

morry329#OP•3w ago

here

TheRanger•3w ago

so it has no namespace is that class in a different project? its fine if it has no namespace, it should detect it atleast, but im thinking that class is in a different project

morry329#OP•3w ago

no, it is in the same project

TheRanger•3w ago

can u prove it

morry329#OP•3w ago

well you have the proof - the screenshot I just sent got the model folder. in there there are two model classes named ListingProjects (I don't use this anymore) and ListingProjects_ver2 (I use) so the error thinks ListingProjects.cs is in the different project then?

TheRanger•3w ago

where is your HomeController.cs ?

morry329#OP•3w ago

Under the Controller folder which is also pictured in my screenshot

TheRanger•3w ago

i see but usually u cant run the program when there are compile errors did you try to recompile the program? if that didnt work try to put a proper namespace for ListingProjects class namespace WebApplication1.Models;

morry329#OP•3w ago

i did - unload and load the project again, dotnet build everything worked without the error

TheRanger•3w ago

if ur done type /close to mark the thread as solved

Gaming

Programming

✅ the type or namespace name 'ListingProjects' does not exist in the namespace models

Did you find this page helpful?