存储过程 .NET Core 和 Entity Framework 的多个返回集

Question

我想从返回 3 个不同表的 SQL Server 存储过程加载 3 个不同的模型，例如：

 select A.id, A.Name from tableA A

 select B.id, B.Age from tableB B

 select C.Test, C.Param from tableC C

通常，我会使用 Entity Framework Core 处理单个结果存储过程，如下所示：

语境：

 public virtual DbQuery<StoredProcedureModel> spModel{ get; set; }

 protected override void OnModelCreating(ModelBuilder modelBuilder)
 {
        modelBuilder.Query<StoredProcedureModel>(entity =>
        {
            entity.Property(e => e.Id)
                    .HasColumnName("Id");
            entity.Property(e => e.Name)
                    .HasColumnName("Name");
        }
 }

存储库：

return _context.StoredProcedureModel
        .FromSql<StoredProcedureModel>(
            "GET_ID_NAME @ID,@NAME",
            new SqlParameter("@ID", ID),
            new SqlParameter("@NAME", Name))
        .ToList();

这只是一个虚拟示例，但我想知道是否有一种方法可以将所有 3 个表加载到 3 个不同的模型中（某些返回的表具有相同的列名称，如“id”）。

Answer 1

目前，Entitiy-Framework 无法实现这一点，但有一个FeatureRequest。作为解决方法，根据这篇博客文章，有一个使用 ADO.Net 的解决方案：

首先对你的类进行编码：

public class TableA 
{
    public int Id { get; set; }
    public string Name { get; set; }
}

public class TableB
{
    public int Id { get; set; }
    public int Age { get; set; }
}

public class TableC
{
    public string Test { get; set; }
    public string Param { get; set; }
}

public class StoredProcedureResult
{
    public List<TableA> TableAEntries { get; set; }
    public List<TableB> TableBEntries { get; set; }
    public List<TableC> TableCEntries { get; set; }
}

然后将以下函数编码到您的 CustomDbContext 类中：

public async Task<StoredProcedureResult> GetStoredProcedureResult(int id, string name)
{
    var connection = Database.GetDbConnection();
    await connection.OpenAsync();

    var command = connection.CreateCommand();
    command.CommandText = "GET_ID_NAME @ID, @NAME";
    command.CommandType = CommandType.StoredProcedure;

    command.Parameters.Add(new Microsoft.Data.SqlClient.SqlParameter("@ID", id));
    command.Parameters.Add(new Microsoft.Data.SqlClient.SqlParameter("@NAME", name));

    var reader = await command.ExecuteReaderAsync();
    var tableAEntries = new List<TableA>();
    var tableBEntries = new List<TableB>();
    var tableCEntries = new List<TableC>();

    while (await reader.ReadAsync())
    {
        tableAEntries.Add(new TableA
        {
            Id = reader.GetInt32("id"),
            Name = reader.GetString("name"),
        });
    }

    await reader.NextResultAsync();

    while (await reader.ReadAsync())
    {
        tableBEntries.Add(new TableB
        {
            Id = reader.GetInt32("id"),
            Age = reader.GetInt32("Age"),
        });
    }

    await reader.NextResultAsync();

    while (await reader.ReadAsync())
    {
        tableCEntries.Add(new TableC
        {
            Test = reader.GetString("Test"),
            Param = reader.GetString("Param"),
        });
    }

    var storedProcedureResult = new StoredProcedureResult();

    storedProcedureResult.TableAEntries = tableAEntries;
    storedProcedureResult.TableBEntries = tableBEntries;
    storedProcedureResult.TableCEntries = tableCEntries;

    await reader.CloseAsync();

    return storedProcedureResult;
}