目前，实体框架无法实现这一点，但存在FeatureRequest。作为一种解决方法，根据此blog post，有一个使用ADO.Net的解决方案：
首先编写类代码：

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;
}