C# 使用多个输出包装多个查询

我有一门课，在这门课上，我正在包装一些简洁的电话，以便做一些类似的事情

var results = SqlWrapper.ExecuteQuery<Product,Customer>("SELECT id FROM Products; SELECT id FROM Customers;");

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下面是一些未经测试的代码，演示了我的一些想法

虽然使用是非常棒的，但是如果您可以选择先创建连接，然后在必要时在finally块中处理sqlConnection，那么您可以减少一些代码。 如果返回一个元组，则可以使用强类型的返回值 如果从不太复杂的函数中调用最复杂的函数，则可以最小化重复的代码。

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我觉得你可能想得太多了。Dapper已经有了一个QueryMultiple方法，您可以使用它来处理多个查询和网格。Read允许您读取结果。是的，我正在将QueryMultiple包装到一个更抽象的类中。这个类还有其他一些东西没有在这里看到，但是这些方法的主要目的是通过一个重载函数来扩展整个网格和读取并无缝支持1-3个结果集

results[0] = List<Product>
results[1] = List<Customer>

using System.Collections.Generic;
using System.Data.SqlClient;
using System.Linq;
using Dapper;

namespace SqlWrapper
{
    public static class SqlWrapper
    {
        private const string SqlConnectionString = "Server=localhost;Database=TTDS;User Id=sa;Password=sa;";


        public static List<T> ExecuteQuery<T>(string sql, object param = null, SqlConnection sqlConnection = null)
        {
            if (sqlConnection != null)
            {
                return sqlConnection.Query<T>(sql, param).ToList();
            }

            using (var tempSqlConnection = new SqlConnection(SqlConnectionString))
            {
                tempSqlConnection.Open();
                return tempSqlConnection.Query<T>(sql, param).ToList();
            }
        }


        public static List<dynamic> ExecuteQuery<T1, T2>(string sql, object param = null, SqlConnection sqlConnection = null)
        {
            if (sqlConnection != null)
            {
                return MultiQuery<T1, T2>(sqlConnection, sql, param);
            }

            using (var tempSqlConnection = new SqlConnection(SqlConnectionString))
            {
                return MultiQuery<T1, T2>(tempSqlConnection, sql, param);
            }
        }

        public static List<dynamic> ExecuteQuery<T1, T2, T3>(string sql, object param = null,
            SqlConnection sqlConnection = null)
        {
            if (sqlConnection != null)
            {
                return MultiQuery<T1, T2, T3>(sqlConnection, sql, param);
            }

            using (var tempSqlConnection = new SqlConnection(SqlConnectionString))
            {
                return MultiQuery<T1, T2, T3>(tempSqlConnection, sql, param);
            }
        }

        private static List<dynamic> MultiQuery<T1, T2>(SqlConnection sqlConnection, string sql, object param = null)
        {
            var rv = new List<dynamic>();

            using (var grid = sqlConnection.QueryMultiple(sql, param))
            {
                rv.Add(grid.Read<T1>().ToList());
                rv.Add(grid.Read<T2>().ToList());
            }

            return rv;
        }

        private static List<dynamic> MultiQuery<T1, T2, T3>(SqlConnection sqlConnection, string sql, object param = null)
        {
            var rv = new List<dynamic>();

            using (var grid = sqlConnection.QueryMultiple(sql, param))
            {
                rv.Add(grid.Read<T1>().ToList());
                rv.Add(grid.Read<T2>().ToList());
                rv.Add(grid.Read<T3>().ToList());
            }

            return rv;
        }


        public static void ExecuteNonQuery(SqlConnection sqlConnection, string sql, object param, int? timeout = null)
        {
            if (sqlConnection != null)
            {
                sqlConnection.Execute(sql, param, commandTimeout: timeout);
            }
            else
            {
                using (var tempSqlConnection = new SqlConnection(SqlConnectionString))
                {
                    tempSqlConnection.Open();
                    tempSqlConnection.Execute(sql, param, commandTimeout: timeout);
                }
            }
        }
    }
}

public static class SqlWrapper
{
    private const string SqlConnectionString = "Server=localhost;Database=TTDS;User Id=sa;Password=sa;";

    private class NoResult { }

    public static List<T1> ExecuteQuery<T1>(string sql, object param = null, SqlConnection sqlConnection = null)
    {
        return ExecuteQuery<T1, NoResult, NoResult>(sql, param, sqlConnection).Item1;
    }

    public static Tuple<List<T1>, List<T2>> ExecuteQuery<T1, T2>(string sql, object param = null, SqlConnection sqlConnection = null)
    {
        var result = ExecuteQuery<T1, T2, NoResult>(sql, param, sqlConnection);
        return Tuple.Create(result.Item1, result.Item2);
    }

    public static Tuple<List<T1>, List<T2>, List<T3>> ExecuteQuery<T1, T2, T3>(string sql, object param = null, SqlConnection sqlConnection = null)
    {
        List<T1> list1;
        List<T2> list2 = null;
        List<T3> list3 = null;
        bool needsDisposed = false;

        if (sqlConnection == null)
        {
            sqlConnection = new SqlConnection(SqlConnectionString);
            sqlConnection.Open();
            needsDisposed = true;
        }

        try
        {
            using (var grid = sqlConnection.QueryMultiple(sql, param))
            {
                list1 = grid.Read<T1>().ToList();
                if (typeof(T2) != typeof(NoResult))
                {
                    list2 = grid.Read<T2>().ToList();
                }
                if (typeof(T3) != typeof(NoResult))
                {
                    list3 = grid.Read<T3>().ToList();
                }

                return Tuple.Create(list1, list2, list3);
            }
        }
        finally { if (needsDisposed) sqlConnection.Dispose(); }
    }


    public static void ExecuteNonQuery(SqlConnection sqlConnection, string sql, object param, int? timeout = null)
    {
        bool needsDisposed = false;

        if (sqlConnection == null)
        {
            sqlConnection = new SqlConnection(SqlConnectionString);
            sqlConnection.Open();
            needsDisposed = true;
        }

        try { sqlConnection.Execute(sql, param, commandTimeout: timeout); }
        finally { if (needsDisposed) sqlConnection.Dispose(); }
    }
}