关于 c#:Database Schema 在 Asp.net Core 2.2 的运行时不变

Database Schema not changing at Runtime in Asp.net Core 2.2 & Entity Framework Core

我有一个应用程序，其中数据保存在不同用户的不同 sql 模式中。

例如

用户 1 数据保存在 SCHEMA1

用户 2 数据保存在 SCHEMA2

以前的应用程序是在 MVC 3 中开发的，它运行良好且符合预期。
现在我们正在迁移 .Net Core 2.2 中的应用程序，其中该功能不起作用
.net 核心没有 IDbModelCacheKeyProvider 因为只有一个模式在工作

下面是 DBContext 文件

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public class ApplicationDbContext : IdentityDbContext<ApplicationUser>
{
//public string Schema { get; set; }
private readonly IConfiguration configuration;
public string SchemaName { get; set; }

public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options)
: base(options)
{

}

public ApplicationDbContext(string schemaname)
: base()
{
SchemaName = schemaname;
}

public DbSet<EmployeeDetail> EmployeeDetail { get; set; }

protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
{
var builder = new ConfigurationBuilder().SetBasePath(Directory.GetCurrentDirectory())
.AddJsonFile("appsettings.json");
var configuration = builder.Build();

optionsBuilder.UseSqlServer(configuration["ConnectionStrings:SchemaDBConnection"]);

var serviceProvider = new ServiceCollection().AddEntityFrameworkSqlServer()
.AddTransient<IModelCustomizer, SchemaContextCustomize>()
.BuildServiceProvider();
}

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.RemovePluralizingTableNameConvention();
modelBuilder.HasDefaultSchema(SchemaName);
base.OnModelCreating(modelBuilder);
}

public string CacheKey
{
get { return SchemaName; }
}

}

public class SchemaContextCustomize : ModelCustomizer
{
public SchemaContextCustomize(ModelCustomizerDependencies dependencies)
: base(dependencies)
{

}
public override void Customize(ModelBuilder modelBuilder, DbContext dbContext)
{
base.Customize(modelBuilder, dbContext);

string schemaName = (dbContext as ApplicationDbContext).SchemaName;
(dbContext as ApplicationDbContext).SchemaName = schemaName;

}
}

我的问题是如何在运行时更改 schemaName

那么组织该机制的正确方法是什么：

通过用户凭据找出架构名称；
从特定模式的数据库中获取用户特定的数据。

相关讨论

我可以通过更改 onConfiguring 方法在运行时更改架构

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public class ApplicationDbContext : IdentityDbContext<ApplicationUser>
{

public string SchemaName { get; set; }

public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options)
: base(options)
{

}

public ApplicationDbContext(string schemaname)
: base()
{
SchemaName = schemaname;
}

public DbSet<EmployeeDetail> EmployeeDetail { get; set; }

protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
{

var builder = new ConfigurationBuilder().SetBasePath(Directory.GetCurrentDirectory())
.AddJsonFile("appsettings.json");
var configuration = builder.Build();

var serviceProvider = new ServiceCollection().AddEntityFrameworkSqlServer()
.AddSingleton<IModelCustomizer, SchemaContextCustomize>()
.BuildServiceProvider();
optionsBuilder.UseSqlServer(configuration["ConnectionStrings:SchemaDBConnection"]).UseInternalServiceProvider(serviceProvider);
}

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
// modelBuilder.MapProduct(SchemaName);

modelBuilder.RemovePluralizingTableNameConvention();
if (!string.IsNullOrEmpty(SchemaName))
{
modelBuilder.HasDefaultSchema(SchemaName);
}
base.OnModelCreating(modelBuilder);
}

public string CacheKey
{
get { return SchemaName; }
}
public class SchemaContextCustomize : ModelCustomizer
{
public SchemaContextCustomize(ModelCustomizerDependencies dependencies)
: base(dependencies)
{

}
public override void Customize(ModelBuilder modelBuilder, DbContext dbContext)
{
base.Customize(modelBuilder, dbContext);

string schemaName = (dbContext as ApplicationDbContext).SchemaName;
(dbContext as ApplicationDbContext).SchemaName = schemaName;

}
}
}