Dapper和匿名类型

16 浏览
0 Comments

Dapper和匿名类型

是否可以在Dapper中使用匿名类型？

我知道可以使用dynamic，例如：

connection.Query(blah, blah, blah)

然后是否可以使用以下方式之一：

.Select(p => new { A, B, C })

或一些变体？

编辑

我想展示一下我目前如何使用Dapper。我倾向于使用一个InMemoryCache来缓存数据，所以我只需要在开始时进行一次大型查询（使用Dapper非常快），然后我使用Linq在我的Repository中对其进行整理。

using System;
using System.Collections.Generic;
using System.Configuration;
using System.Data.Common;
using System.Linq;
using Dapper;
namespace SomeNamespace.Data
{
public class DapperDataContext : IDisposable
{
    private readonly string _connectionString;
    private readonly DbProviderFactory _provider;
    private readonly string _providerName;
    public DapperDataContext()
    {
        const string connectionStringName = " DataContextConnectionString";
        _connectionString = ConfigurationManager.ConnectionStrings[connectionStringName].ConnectionString;
        _providerName = ConfigurationManager.ConnectionStrings[connectionStringName].ProviderName;
        _provider = DbProviderFactories.GetFactory(_providerName);
    }
    public IEnumerable MyData1 { get; private set; }
    public IEnumerable MyData2 { get; private set; }
    protected string SqlSelectMyTable1Query
    {
        get
        {
            return @"SELECT Id, A, B, C from table1Name";
        }
    }   
protected string SqlSelectMyTable2Query
{
    get
    {
    return @"SELECT Id, A, B, C from table2Name";
    }
    }
    public void Dispose()
    {
    }
    public void Refresh()
    {
        using (var connection = _provider.CreateConnection())
        {
            // 如果为null则抛出异常
            connection.ConnectionString = _connectionString;
            connection.Open();
            var sql = String.Join(" ",
                            new[]
                                {
                                    SqlSelectMyTable1Query,
                                    SqlSelectMyTable2Query
                                });
            using (var multi = connection.QueryMultiple(sql))
            {
                MyData1 = multi.Read().ToList();
                MyData2 = multi.Read().ToList();
            }
        }
    }
    public class MyDataView
    {
        public long Id { get; set; }
        public string A { get; set; }
        public string B { get; set; }
        public string C { get; set; }
    }      
}
}

InMemoryCache看起来像这样

namespace Libs.Web
{
public class InMemoryCache : ICacheService
{
    #region ICacheService Members
    public T Get(string cacheId, Func getItemCallback) where T : class
    {
        var item = HttpRuntime.Cache.Get(cacheId) as T;
        if (item == null)
        {
            item = getItemCallback();
            HttpContext.Current.Cache.Insert(cacheId, item);
        }
        return item;
    }
    public void Clear(string cacheId)
    {
        HttpContext.Current.Cache.Remove(cacheId);
    }
    #endregion
}
public interface ICacheService
{
    T Get(string cacheId, Func getItemCallback) where T : class;
    void Clear(string cacheId);
}
}

0