C# MVVM ASP.net API implicit conversion error

Question

New to web app API's and trying to build a web app that exposes data from our DWH environment to the application via an API.

My models:

bed_data_dbconnect - context model:

 using Microsoft.EntityFrameworkCore; namespace BED_MGMT_WEBAPP_APIs.Models { public class bed_data_dbconnect : DbContext { public bed_data_dbconnect(DbContextOptions options) : base(options) { } public DbSet<Bed_Data> tblBase_BEDMGMT_BEDS_BY_WARD { get; set; } } } 

bed_data model

 using System; namespace BED_MGMT_WEBAPP_APIs.Models { public class Bed_Data { public string HOSPITAL {get;set;} public string WARD_CODE {get;set;} public string WARD {get;set;} public string REALTIME_BED_STOCK {get;set;} public string ACTUAL_BED_STOCK {get;set;} public string AVAILABLE_BEDS_M {get;set;} public string AVAILABLE_BEDS_F {get;set;} public string AVAILABLE_BEDS_C {get;set;} public string TOTAL_BEDS_CLOSED {get;set;} public string CLOSED_AND_UNOCCUPIED {get;set;} public string ESCALATION_BEDS_IN_USE {get;set;} public string DISCHARGES_CONFIRMED_M {get;set;} public string DISCHARGES_CONFIRMED_F {get;set;} public string DISCHARGES_CONFIRMED_C {get;set;} public string DISCHARGES_POTENTIAL_M {get;set;} public string DISCHARGES_POTENTIAL_F {get;set;} public string DISCHARGES_POTENTIAL_C {get;set;} public string AWAITING_ADMISSION_AE_M {get;set;} public string AWAITING_ADMISSION_AE_F {get;set;} public string AWAITING_ADMISSION_AE_C {get;set;} public string AWAITING_ADMISSION_INTERNAL_M {get;set;} public string AWAITING_ADMISSION_INTERNAL_F {get;set;} public string AWAITING_ADMISSION_INTERNAL_C {get;set;} public string AWAITING_ADMISSION_EXTERNAL_M {get;set;} public string AWAITING_ADMISSION_EXTERNAL_F {get;set;} public string AWAITING_ADMISSION_EXTERNAL_C {get;set;} public string AWAITING_REPATRIATION_IN {get;set;} public string AWAITING_REPATRIATION_OUT {get;set;} public string OUTLIERS_MED {get;set;} public string OUTLIERS_SURG {get;set;} public string OUTLIERS_ORTH {get;set;} public string STAFFING_SHORTAGES {get;set;} public string USER_CODE {get;set;} public string DATETIME_RECORD_INSERTED {get;set;} //= System.Convert.ToDateTime() } } 

db connection string in my startup file:

 public void ConfigureServices(IServiceCollection services) { string connectionString = Configuration.GetConnectionString("DefaultConnection"); services.AddDbContext<bed_data_dbconnect>(opt => opt.UseSqlServer(connectionString)); services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_3_0); } 

Controller:

 using Microsoft.AspNetCore.Mvc; using System.Collections.Generic; using System.Linq; using BED_MGMT_WEBAPP_APIs.Models; namespace BED_MGMT_WEBAPP_APIs.Controllers { [Route("api/[Controller]")] [ApiController] public class bed_data_controller : Controller { private bed_data_dbconnect _bed_data; public bed_data_controller(bed_data_dbconnect context) { _bed_data = context; } //Get api/values [HttpGet] public ActionResult<IEnumerable<bed_data_dbconnect>> Get() { return _bed_data.tblBase_BEDMGMT_BEDS_BY_WARD.ToList(); } ~bed_data_controller() { _bed_data.Dispose(); } } } 

I am trying to return the contents of this table to a list to validate the api is working as expected, but the controller above generates an error:

Cannot implicitly convert type 'System.Collections.Generic.List' to 'Microsoft.AspNetCore.Mvc.ActionResult>' [BED_MGMT_WEBAPP_APIs]

on this line:

 return _bed_data.tblBase_BEDMGMT_BEDS_BY_WARD.ToList(); 

Answer 1

You can try it like this:

[HttpGet] public ActionResult Get() { var result=_bed_data.tblBase_BEDMGMT_BEDS_BY_WARD.ToList(); return Json(result); } 

Answer 2

I expect the returntype of your endpoint is wrong. The returntype of your endpoint is ActionResult<IEnumerable<bed_data_dbconnect>>.

Where bed_data_dbconnect is a DbContext class.

Shouldn't the returntype be ActionResult<IEnumerable<Bed_Data>>?