How to get connection from startup to static class Data access?

Question

User696604810 posted

I work on asp.net core 2.2 vs2017 app I face issue I cannot get connection string from start up to static Data access class 

class CZConnection
  public class CZConnection
    {


        public string DashboardConnection { get; set; }

    
    }
StartUp.cs
services.Configure<CZConnection>(DBConnection =>
            {
              
                DBConnection.DashboardConnection = Configuration.GetConnectionString("DashBoardSQLConnection");



            });

public static partial class DataAccess
{
  static SqlConnection InitializeConnection()
    {
     
          
               
                return new SqlConnection(here I need to get connection string of DBConnection.DashboardConnection);
             


        }
        return new SqlConnection();

 
}

Answer 1

User1120430333 posted

The fact that you are even trying to use a static class in .NET Core is questionable. Static class causes 'static clng' that results in tightly coupled code and not clean coding.

https://objcsharp.wordpress.com/2013/07/08/why-static-code-is-bad/

https://docs.microsoft.com/en-us/archive/msdn-magazine/2016/may/asp-net-writing-clean-code-in-asp-net-core-with-dependency-injection

You could look into using the info in the link. As long as you can access the appsetting.json, you don't need to have your data access class in a classlib project.

https://corderoski.wordpress.com/2017/09/18/how-to-read-appsettings-json-from-class-library-in-asp-net-core/

Answer 2

User-2054057000 posted

You can put the connection string in appsetttings.json and then do it's configuration in ConfigureServices() method of Startup.cs:

public void ConfigureServices(IServiceCollection services)
        {
            services.AddDbContext<AppIdentityDbContext>(options => options.UseSqlServer(Configuration["ConnectionStrings:DefaultConnection"]));
            services.AddMvc();
        }

Kindly refer this tutorial for help.

Answer 3

User696604810 posted

OK I need way to pass connection to class public 

suppose I have class as below 

public  partial class DataAccess
{
  public SqlConnection InitializeConnection()
    {
     
          
               
                return new SqlConnection(here I need to get connection string of DBConnection.DashboardConnection);
             


        }
        return new SqlConnection();

 
}

How to get connection to public class as above please ?

Answer 4

User-2054057000 posted

OK I need way to pass connection to class public 

You need to do it by injecting it to the controller through Dependency Injection. Check the tutorial link I gave you.

Answer 5

User-474980206 posted

the preferred approach is to inject the configuration:

public class DataAcessOptions
{
   public string ConnectionString {get; set;}
   // other options
}

public  partial class DataAccess
{
  private DataAcessOptions _options;

  public DataAccess(DataAcessOptions options)
  {
      _options = options;
  }

  public Task<SqlConnection> InitializeConnection()
  {
  }
}
 

also for asp.net core, you should always use async sql operations. 

Answer 6

User696604810 posted

thank you for reply

this require register as service on startup meaning must create interface for service on startup.cs or no need 

startup.cs

addscroped<idataaccess,dataaccess>

or no need

Answer 7

User1120430333 posted

thank you for reply

this require register as service on startup meaning must create interface for service on startup.cs or no need 

startup.cs

addscroped<idataaccess,dataaccess>

or no need

I am getting the connectionstring and passing DI all the way through the classes to where I need the connectionstring, by using Microsoft.Extensions.Options;

https://docs.microsoft.com/en-us/aspnet/core/fundamentals/configuration/options?view=aspnetcore-3.1

I gave you the link on how to do it in my first post.

In startup.cs Configuration service method

//Configuration
 services.Configure<ConnectionStrings>(Configuration.GetSection("ConnectionStrings"));

namespace Entities
{
    public class ConnectionStrings
    {
        public string DefaultConnection { get; set; }
        public string ProjectManagementConnection { get; set; }
    }
}

{
  "ConnectionStrings": {
    "DefaultConnection": "Dummy",
    "ProjectManagementConnection":
      "Server=DESKTOP-A86QNRQ\\SQLEXPRESS;Database=ProjectManagement;User Id=SA;Password=xxxxxxxxx"
  },
  "Serilog": {
    "Using": ["Serilog.Sinks.Console"],
    "MinimumLevel": "Error",
    "WriteTo": [
      { "Name": "Console" },
      {
        "Name": "RollingFile",
        "Args": {
          "pathFormat": "c:\\logsapi\\log-{Date}.txt",
          "outputTemplate": "{Timestamp:yyyy-MM-dd HH:mm:ss.fff zzz} [{Level}] {Message}{NewLine}{Exception}"
        }
      }
    ],
    "Enrich": ["FromLogContext", "WithMachineName", "WithThreadId"],
    "Properties": {
      "Application": "My Application",
      "Logging": {
        "LogLevel": {
          "Default": "Warning"
        }
      },
      "AllowedHosts": "*"
    }
  }
}

using Entities;
using Microsoft.Extensions.Options;

namespace DAL
{
    public class AppConfiguration
    {
        private readonly string _projectManagementConnection = "";
        private readonly IOptions<ConnectionStrings> _options;

        public AppConfiguration(IOptions<ConnectionStrings> options) 
        {
            _options = options;
            _projectManagementConnection = _options.Value.ProjectManagementConnection;
        }

        public string GetProjectMgmntConn() => $"{_projectManagementConnection}";

    }
}

using System.Collections.Generic;
using System.Linq;
using System.Transactions;
using DAL.Models.DB;
using Entities;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Options;

namespace DAL
{
    public class DaoProject :IDaoProject
    {
        private readonly IOptions<ConnectionStrings> _options;
        
        public DaoProject(IOptions<ConnectionStrings> options)
        {
            _options = options;
        }

        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;
        }

using Entities;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Options;

namespace DAL.Models.DB
{
    public partial class ProjectManagementContext : DbContext
    {
        private readonly IOptions<ConnectionStrings> _options;
        public ProjectManagementContext(IOptions<ConnectionStrings> options)
        {
            _options = options;
        }

        public ProjectManagementContext(DbContextOptions<ProjectManagementContext> options)
            : base(options)
        {
        }

        public virtual DbSet<Projects> Projects { get; set; }
        public virtual DbSet<Tasks> Tasks { get; set; }
        public virtual DbSet<ProjectTypes> ProjectTypes { get; set; }
        public virtual DbSet<Durations> Durations { get; set; }
        public virtual DbSet<Resources> Resources { get; set; }
        public virtual DbSet<Statuses> Statuses { get; set; }

        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        {
            if (!optionsBuilder.IsConfigured)
            {
                optionsBuilder.UseSqlServer(new AppConfiguration(_options).GetProjectMgmntConn());
            }