I am new to ASP.NET and I am creating a Web API using sort of code first. I have model class call gender and defined as follow
public class Gender
{
public int Id { get; set; }
public string Description { get; set; }
}
I decided to create a new folder call DBContext and inside will defined all my DBContext, so for the gender class I have created GenderDb and look like follow:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Data.Entity;
namespace BackAPI.Models
{
public class GenderDB : DbContext
{
// not define yet
}
}
However I am having an issue however with DbContext not being defined, apparently I am supposed to use Entity Framework, however I want to create my database not through Visual Studio, but using SQL Server 2014 Express.
I did add my data connection and can see that I created a table in SQL Server, however how do I fix DbContext, if I use EF wouldn't that just create it locally and that not what I want
Entity Framework, along with Migrations, will help you here.
I suggest you check out this tutorial: Code First to a New Database
Related
I am trying to use Dapper.Contrib to extend the functionality of the IDbConnection interface with, amongst others, the .insert() method.
To do so, I have followed the somewhat brief and scattered documentation here and here. In short, I have used NuGet to add Dapper and Dapper.Contrib to my project, I have added using Dapper; and using Dapper.Contrib; at the top of my Repository class, and I am using System.Data.SqlClient.SqlConnection() to create an IDbConnection.
Still, my connection object does not have the extended methods available. For example, when trying to use the .insert() method, I get the message:
'IDbConnection' C# does not contain a definition for 'Insert' and no
extension method 'Insert' accepting a first argument of type could be
found (are you missing a using directive or an assembly reference?)
This is in an ASP.NET Core 2.0 project using Razor Pages.
For completeness sake, you can find the Repository class below.
Maybe interesting to note, is that the using lines for Dapper and Dapper.Contrib are grayed out...
Also, of course I have a (very minimalistic) Model Class for the TEST Entity, containing one parameter, TEST_COLUMN, annotated with [Key].
using Dapper.Contrib;
using Dapper;
using Microsoft.Extensions.Configuration;
using TestProject.Model;
using System;
using System.Collections.Generic;
using System.Data;
using System.Data.SqlClient;
using System.Linq;
using System.Threading.Tasks;
namespace TestProject.Repository
{
public class TEST_Repository
{
IConfiguration configuration;
public TEST_Repository(IConfiguration configuration)
{
this.configuration = configuration;
}
public void Insert()
{
using (var con = this.GetConnection())
{
con.Insert(new TEST { TEST_COLUMN = "test" });
}
}
public IDbConnection GetConnection()
{
return new SqlConnection(configuration.GetSection("ConnectionStrings").GetSection("DefaultConnection").Value);
}
}
}
The Insert method you are looking for lives inside of the Dapper.Contrib.Extensions namespace, as can be seen in the source, included for completeness:
namespace Dapper.Contrib.Extensions
{
...
public static long Insert<T>(this IDbConnection connection, ...)
...
}
Hence, in order to use the Extension methods, you should add the following line to your code:
using Dapper.Contrib.Extensions;
AWS CodePipeline allows you to invoke a custom Lambda from an action as described here, https://docs.aws.amazon.com/codepipeline/latest/userguide/actions-invoke-lambda-function.htmltion
I am having trouble determining how my C# Lambda function should be defined in order to access the input data from the pipeline.
I tried numerous attempts, was thinking it would be something similar to below. I have also tried to create my own C# classes that the input JSON data would be deserialized to.
public void FunctionHandler( Amazon.CodePipeline.Model.Job
CodePipeline, ILambdaContext context)
I was able to find out a solution. Initially the first step that helped was to change the input parameter for my lambda function to a Stream. I was then able to convert the stream to a string and determine exactly what was being sent to me, e.g
public void FunctionHandler(Stream input, ILambdaContext context)
{
....
}
Then, based on the input data I was able to map it to a C# class that wrapped the AWS SDK Amazon.CodePipeline.Model.Job class. It had to be mapped to the json property "CodePipeline.job". The below code worked, I was able to retrieve all input values.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Amazon.Lambda.Core;
using Amazon.CodePipeline;
using Newtonsoft.Json;
using System.IO;
// Assembly attribute to enable the Lambda function's JSON input to be converted into a .NET class.
[assembly: LambdaSerializer(typeof(Amazon.Lambda.Serialization.Json.JsonSerializer))]
namespace lambdaEmptyFunction
{
public class Function
{
public class CodePipelineInput
{
[JsonProperty("CodePipeline.job")]
public Amazon.CodePipeline.Model.Job job { get; set; }
}
public void FunctionHandler(CodePipelineInput input, ILambdaContext context)
{
context.Logger.LogLine(string.Format("data {0} {1} {2}", input.job.AccountId, input.job.Data.InputArtifacts[0].Location.S3Location.BucketName, input.job.Id));
}
}
}
Like the title says, I am trying to connect a new MVC 5 app created by Visual Studio 2013 to an existing database table created by and Azure Mobile Service.
I realized that the issue was with the schema of the tables that were created by the mobile service. Instead of using the default "dbo" schema, the tables used <mobile_service_name> as the schema. My MVC project was looking for dbo.<Table_Name> instead of <mobile_service_name>.<Table_Name> and was throwing an error as a result. To fix this, you need to add some mappings in you DB Context class to tell it where exactly to find the tables it is looking for. These mappings are done in an overridden method called OnModelCreating. It ends up looking like this:
public class ApplicationDbContext : IdentityDbContext<ApplicationUser>
{
public ApplicationDbContext() : base("DefaultConnection")
{
}
public System.Data.Entity.DbSet<MyObject> MyObjects { get; set; }
protected override void OnModelCreating(System.Data.Entity.DbModelBuilder modelBuilder)
{
base.OnModelCreating(modelBuilder);
modelBuilder.Entity<MyObject>().ToTable("<mobile_service_name>.<Table_Name>");
}
}
I am attempting to figure out how to host MVC4 apps that were built under different solutions. There are many examples of doing this on SO and on the web using the RazorGenerator nuget package with Areas - it works very well. In my situation, I want to avoid using areas - every application my company develops will be in it's own MVC4 project (then collectively in the same solution).
I've integrated RazorGenerator into my apps, the code gen is working as expected. However, my host solution can not find the View in it's default locations. As an example, I have a Controller/View built in one app called MyAccount/Index.
Controller:
namespace Accounts.Controllers
{
public class MyAccountController : Controller
{
//
// GET: /MyAccount/
public ActionResult Index()
{
return View();
}
}
}
View (as generated from RazorGenerator):
namespace Accounts.Views.MyAccount
{
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Text;
using System.Web;
using System.Web.Helpers;
using System.Web.Mvc;
using System.Web.Mvc.Ajax;
using System.Web.Mvc.Html;
using System.Web.Routing;
using System.Web.Security;
using System.Web.UI;
using System.Web.WebPages;
[System.CodeDom.Compiler.GeneratedCodeAttribute("RazorGenerator", "1.5.4.0")]
[System.Web.WebPages.PageVirtualPathAttribute("~/Views/MyAccount/Index.cshtml")]
public partial class Index : System.Web.Mvc.WebViewPage<dynamic>
{
public Index()
{
}
public override void Execute()
{
#line 1 "..\..\Views\MyAccount\Index.cshtml"
ViewBag.Title = "Index";
#line default
#line hidden
WriteLiteral("\r\n\r\n<h2>Index</h2>\r\n\r\nMy AccountController Index view.");
}
}
}
I know that by default, the ViewEngines are going to try to find this view in the default locations (Views and Shared), so I added my own ViewEngine to the Engines collection:
MyViewEngine.cs:
public class MyViewEngine : RazorViewEngine
{
private static string[] _viewLocations
= new string[]
{
"~/Accounts/Views/{1}/{0}.cshtml"
};
public MyViewEngine()
{
base.ViewLocationFormats = ViewLocationFormats.Union(_viewLocations).ToArray();
}
}
However, the view still isn't found:
The view 'Index' or its master was not found or no view engine supports the searched locations.
The following locations were searched:
~/Views/MyAccount/Index.cshtml
~/Views/Shared/Index.cshtml
~/Views/MyAccount/Index.aspx
~/Views/MyAccount/Index.ascx
~/Views/Shared/Index.aspx
~/Views/Shared/Index.ascx
~/Views/MyAccount/Index.vbhtml
~/Views/Shared/Index.vbhtml
~/Accounts/Views/MyAccount/Index.cshtml
Maybe I am misunderstanding how the view is located -I had thought it would have been found in Accounts/Views/MyAccount/. Any ideas what I might be doing wrong?
Thanks!
Found my issue - it was due to not having the RazorGeneratorMvcStart warmup code in place. It is generated automatically into the App_Start folder when you add the nuget package, however I erroneously removed it.
I'm developing an ASP.NET MVC 4 application. Getting information from the database and displaying it on the webpage went well at this stage. Then I decided I'd like to develop a Web API as well side-by-side with my application's progress. So far so good, until I tried to test it using a URL on the local host.
When I tried it out, I got an HTTP Error 500.
I ran the application from VS 2010 and it opened up http://localhost:23375/ in my browser. At the end of this, I appended my API call, bringing it to:
http://localhost:23375/api/Performance/ShowMachines
When I hit enter, I get the error. Why is this so and how can I resolve it?
Here is the relevant code:
PerformanceController.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Web.Http;
using PerfMon.Models;
namespace PerfMon.Controllers
{
public class PerformanceController : ApiController
{
PerfMonDataRepository perfRep = new PerfMonDataRepository();
// GET /performance/machines
[HttpGet]
public IQueryable<Machine> ShowMachines()
{
return perfRep.GetAllMachines();
}
}
}
Global.asax.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Http;
using System.Web.Mvc;
using System.Web.Optimization;
using System.Web.Routing;
namespace PerfMon
{
// Note: For instructions on enabling IIS6 or IIS7 classic mode,
// visit http://go.microsoft.com/?LinkId=9394801
public class WebApiApplication : System.Web.HttpApplication
{
protected void Application_Start()
{
AreaRegistration.RegisterAllAreas();
FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
RouteConfig.RegisterRoutes(RouteTable.Routes);
BundleConfig.RegisterBundles(BundleTable.Bundles);
}
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.MapHttpRoute(
name: "Machines",
routeTemplate: "api/{controller}/{action}",
defaults: new {
controller = "Performance",
action = "ShowMachines"
}
);
}
}
}
I'm running into the same problem and I think I narrowed it down to the Accept header of HTTP. When you make a call to the API via JavaScript passing the Accept header as JSON or XML it works.
When you make the call from the browser, you are asking for different content types, therefore you get an error 500.
I still couldn't confirm it, but looks like that.
The issue was that when I created the .dbml file, and dragged and dropped the table into it, the automatically generated DataContext class created EntitySet objects to represent the foreign-key relationships. I created simple classes with gets sand sets to return the JSON, rather than the classes in the DataContext, excluding the EntitySet objects. As a result, it worked like a charm. Apparently EntitySets are not serializeable, and thus were giving the 500 Error.