c# - 使用 appsettings.json 配置 DbContext 映射

Question

我正在使用 .netCore 和 Entity Framework 从 SQL 数据库获取一些数据。
我已经设置了一个DbContext

public partial class DashboardContext : DbContext
{
    public NotfallDashboardContext(DbContextOptions<NotfallDashboardContext> options) : base(options) {}

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.Entity<DashboardData>(entity =>
        {
            ...
        }
    }

    public virtual DbSet<DashboardData> DashboardData { get; set; }
}

并使用以下设置将其注入(inject)我的 Controller

services.AddDbContext<DashboardContext>(options => options.UseSqlServer(Configuration.GetConnectionString("DashboardDatabase")));

现在，DashboardData 类使用 Table Attirbute 连接到正确的表和架构。

[Table("TableName", Schema = "dbo")]
public partial class DashboardData
{
    ...
}

---

What i would like to do, is to extract these two strings "TableName" and "dbo" into my appsettings.json configuration. I already added the configuration to appsettings, made a TableConfiguration class and setup dependency injection:

表配置.cs

public class TableConfiguration
{
    public string DatabaseView { get; set; }
    public string DatabaseSchema { get; set; }
}

appsettings.json

"TableConfiguration": {
    "DatabaseTable": "TableName",
    "DatabaseSchema": "dbo"
} 

启动.cs

services.Configure<TableConfiguration>(Configuration.GetSection("TableConfiguration"));

Is it possible to inject or otherwise use the configuration in the DasboardData Attribute?

Answer 1

在您的 Startup.cs 中:

services.Configure<TableConfiguration>(Configuration.GetSection("TableConfiguration"));

然后，注入(inject)IOptions<TableConfiguration> tableConf到您的上下文中并将其存储以供您的 OnModelCreating() 稍后使用:

public class DashboardContext : DbContext
{
    private readonly TableConfiguration tableConf;

    public DashboardContext(DbContextOptions<DashboardContext> options, IOptions<TableConfiguration> tableConf) : base(options)
    {
        this.tableConf = tableConf.Value;
    }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.Entity<DashboardData>(entity =>
        {
            entity.ToTable(this.tableConf.DatabaseTable, this.tableConf.DatabaseSchema);
        });
    }

    public virtual DbSet<DashboardData> DashboardData { get; set; }
}