我该如何解决这个错误 CS0311 ASP.Net Core API

Question

Startup.cs 类

namespace API
{
    public class Startup
    {
        public IConfiguration _Config { get; }

        public Startup(IConfiguration config)
        {
            _Config = config;
        }

       

        // This method gets called by the runtime. Use this method to add services to the container.
        public void ConfigureServices(IServiceCollection services)
        {
            services.AddDbContext<DataContext>(options => 
            {
            options.UseSqlite(_Config.GetConnectionString("DefaultConnection"));
            });
           
            services.AddControllers();
            services.AddSwaggerGen(c =>
            {
                c.SwaggerDoc("v1", new OpenApiInfo { Title = "API", Version = "v1" });
            });
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
                app.UseSwagger();
                app.UseSwaggerUI(c => c.SwaggerEndpoint("/swagger/v1/swagger.json", "API v1"));
            }

            app.UseHttpsRedirection();

            app.UseRouting();

            app.UseAuthorization();

            app.UseEndpoints(endpoints =>
            {
                endpoints.MapControllers();
            });
        }
    }
}

DataContext.cs 类

using API.Entities;
using Microsoft.EntityFrameworkCore;

namespace API.Data
{
    public class DataContext : DbContext
    {
        public DataContext( DbContextOptions options) : base(options)
        {
        }

        public DbSet<AppUser> Users { get; set; }
    }
}

Users/sakeeljawfer/Desktop/ASP/DatingApp/API/Startup.cs(34,22)：错误 CS0311：类型“API.Data.DataContext”不能用作泛型类型中的类型参数“TContext”或方法'EntityFrameworkServiceCollectionExtensions.AddDbContext（IServiceCollection，Action，ServiceLifetime，ServiceLifetime）'。没有从“API.Data.DataContext”到“Microsoft.EntityFrameworkCore.DbContext”的隐式引用转换。 [/Users/sakeeljawfer/Desktop/ASP/DatingApp/API/API.csproj]

Answer 1

您必须将 DataContext 类修复为：

public class DataContext : DbContext
{ 
public DataContext() 
{
}
        
public DataContext( DbContextOptions<DataContext> options) : base(options)    
{
}          
.....