asp.net web api 2 can not query with lambda

Question

User-1104215994 posted

Hello,

I am trying to query the database with a username from the request. But I am getting this error; The type 'Func<,>' is defined in an assembly that is not referenced. You must add a reference to assembly '<g class="gr_ gr_124 gr-alert gr_spell gr_inline_cards gr_run_anim ContextualSpelling ins-del multiReplace" id="124" data-gr-id="124">netstandard</g>. How can I fix this?

Here is a portion of my controller:

[RoutePrefix("api/v3/token")]
    public class CompaniesController : ApiController
    {
        private EPINMiddleWareAPIContext context;

        public CompaniesController(EPINMiddleWareAPIContext context)
        {
            this.context = context;
        }
       
        
        // POST: api/Companies
        [ResponseType(typeof(Company))]
        [HttpPost, Route("company")]
        public async Task<IHttpActionResult> Company(Company company)
        {
            if (!ModelState.IsValid)
            {
                return BadRequest(ModelState);
            }

            
            context.Companies.Add(company);
            await context.SaveChangesAsync();

           var c = context.Companies.FirstOrDefault<Company>(p => p.userName == company.userName);

            IHttpActionResult response;
            HttpResponseMessage responseMsg = new HttpResponseMessage();
            bool isUsernamePasswordValid = false;
...

Here is my model:

public class Company
    {
        public int Id { get; set; }
        [Required]
        public string userName { get; set; }
        [Required]
        public string hash { get; set; }
        [Required]
        public string salt { get; set; }
        [Required]
        public int customerID { get; set; }
    }

Best Regards.

Answer 1

User475983607 posted

Remove company...  it is redundant.

 var c = context.Companies.FirstOrDefault(p => p.userName == company.userName);

You are missing a reference.  Is this an ASP.NET Core application?

https://github.com/dotnet/standard/issues/542

Answer 2

User-1104215994 posted

same error;

Severity Code Description Project File Line Suppression State
Error CS0012 The type 'Func<,>' is defined in an assembly that is not referenced. You must add a reference to assembly 'netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51'.

Answer 3

User475983607 posted

same error;

Severity Code Description Project File Line Suppression State
Error CS0012 The type 'Func<,>' is defined in an assembly that is not referenced. You must add a reference to assembly 'netstandard, Version=2.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51'.

You are missing a reference.  If this is an ASP.NET Core application and a separate assembly, add the netstandard the project file.

Answer 4

User-1104215994 posted

You are missing a reference.  Is this an ASP.NET Core application?

asp.net web <g class="gr_ gr_26 gr-alert gr_spell gr_inline_cards gr_run_anim ContextualSpelling ins-del multiReplace" id="26" data-gr-id="26">api</g> 2

Answer 5

User475983607 posted

cenk1536

asp.net web api 2

The error is very clear.  It seems you built a netstandard library.  Please review your work.

https://docs.microsoft.com/en-us/dotnet/standard/net-standard

Also the code looks like ASP.NET Core constructor injection. Are you sure?

Answer 6

User1120430333 posted

Why don't you just use the Where clause? The examples are using EF core. 

public DtoProject GetProjectById(int id)
        {
            var dto = new DtoProject();

            using (var context = new ProjectManagementContext(_options))
            {
                var project = (context.Projects.Where(a => a.ProjectId == id)).SingleOrDefault();

                if (project == null) return dto;
                dto.ProjectId = project.ProjectId;
                dto.ClientName = project.ClientName;
                dto.ProjectName = project.ProjectName;
                dto.Technology = project.Technology;
                dto.ProjectType = project.ProjectType;
                dto.UserId = project.UserId;
                dto.StartDate = project.StartDate;
                dto.EndDate = project.EndDate;
                dto.Cost = project.Cost;
            }

            return dto;
        }

public List<DtoProject> GetProjectsByUserId(string userid)
        {
            var dtos = new List<DtoProject>();

            using (var context = new ProjectManagementContext(_options))
            {
                
                dtos = (from a in context.Projects.Where(a => a.UserId.Contains(userid))
                    select new DtoProject
                    {
                        ProjectId = a.ProjectId,
                        ClientName = a.ClientName,
                        ProjectName = a.ProjectName,
                        Technology = a.Technology,
                        ProjectType = a.ProjectType,
                        UserId = a.UserId,
                        StartDate = a.StartDate,
                        EndDate = a.EndDate,
                        Cost = a.Cost
                    }).ToList();
            }

            return dtos;
        }

Answer 7

User-1104215994 posted

Why don't you just use the Where clause? The examples are using EF core. 

I will try and let you know.

Answer 8

User-1104215994 posted

Adding <Reference Include="<g class="gr_ gr_25 gr-alert gr_spell gr_inline_cards gr_run_anim ContextualSpelling ins-del multiReplace" id="25" data-gr-id="25">netstandard</g>" /> to <g class="gr_ gr_26 gr-alert gr_spell gr_inline_cards gr_run_anim ContextualSpelling" id="26" data-gr-id="26">csproj</g> file solved the issue. And where clause also worked.