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实体框架核心添加迁移提供的值不能为空(参数'connectionString')

ef-code-first entity-framework-core asp.net-core c#

0

Caverman · 技术社区 · 6 年前

值不能为空(参数'connectionString')

ConnectionStrings 在 appsetttings.json 文件。不过,我已经找遍了我的,并尝试了几个复制/粘贴,以确保我有正确的拼写。要么是别的原因,要么是我看了太多,忽略了什么。

Appsettings.json文件

{
    "ConnectionStings": {
        "DbConnection": "Server=DAVIDPC\\SQLEXPRESS01;Database=dotnet-rpg;Trusted_Connection=true;MultipleActiveResultSets=true;"
    },
    "Logging": {
        "LogLevel": {
            "Default": "Information",
            "Microsoft": "Warning",
            "Microsoft.Hosting.Lifetime": "Information"
        }
    },
    "AllowedHosts": "*"
}

启动.cs

public Startup(IConfiguration configuration)
{
    Configuration = configuration;
}

public IConfiguration Configuration { get; }

// This method gets called by the runtime. Use this method to add services to the container.
public void ConfigureServices(IServiceCollection services)
{
    services.AddDbContext<DataContext>(x => x.UseSqlServer(Configuration.GetConnectionString("DbConnection")));
    services.AddControllers();
    services.AddAutoMapper(typeof(Startup));
    services.AddScoped<ICharacterService, CharacterService>();
}

1 回复 | 直到 6 年前

1

3

olk 6 年前

在你的例子中你拼错了 连接字符串

 {
        "ConnectionStings": {
            "DbConnection": "Server=DAVIDPC\\SQLEXPRESS01;Database=dotnet-rpg;Trusted_Connection=true;MultipleActiveResultSets=true;"
        },
        "Logging": {
            "LogLevel": {
                "Default": "Information",
                "Microsoft": "Warning",
                "Microsoft.Hosting.Lifetime": "Information"
            }
        },
        "AllowedHosts": "*"
    }

2

0

Karthik 6 年前

应用程序设置和配置服务方法看起来不错。试试这个

  "ConnectionStrings": {
    "DbContext": "Data Source=(LocalDb)\\MSSQLLocalDB;Initial Catalog=dotnet-rpg;Integrated Security=SSPI; MultipleActiveResultSets=true;",
    "Logging": {
      "LogLevel": {
        "Default": "Information",
        "Microsoft": "Warning",
        "Microsoft.Hosting.Lifetime": "Information"
      }
    }
  }

services.AddDbContextPool<DataContext>(options =>
            options.UseSqlServer(Configuration.GetConnectionString("DbContext"))
            );

如果这解决了你的问题,请告诉我。

下面两个参考链接有实现细节。

Implement create, read, update, and delete functionalities using Entity Framework Core

Configure Azure SQL relational database using vs 2019