接觸PetaPoco已經有一段時間了,為了全面了解一下PetaPoco,剛好結合目前在做的一個項目,對常用的幾個業務操作用PetaPoco進行改寫,如增刪改查、分頁以及存儲過程的調用,在文章的最后附上我測試的源碼(源碼有許多不規范的地方,也有冗余,只是簡單地改寫后為了快速通過函數功能測試,希望大家拍磚指正。)
1、 PetaPoco是C#微型ORM框架,基本無需配置,僅由單個cs文件構成,支持.net3.5 .net4.0。官方還出品了配套的T4模板用來自動生成數據庫Models。官方網站:http://www.toptensoftware.com/petapoco/,截稿時PetaPoco的官方最新版本為5.0.1。
2、 從官網下載文件壓縮包(另一種安裝PetaPoco文件的方式見本文的最后的附錄一),下載地址需要注意一下,官方給出的Github下載地址是https://github.com/toptensoftware/PetaPoco,如果你點這個地址下載下來的可能是前一個版本,也就是4.0.3,我個人是遇到這個問題了,以為下載下來的是5.0.1,其實不然,下面給出一個能下載到5.0.1的地址,也是Github上的https://github.com/toptensoftware/PetaPoco/tree/v5,打開鏈接之后點擊右邊下載zip包即可。(順帶也提醒一下,官網給出的NuGet下載地址,沒有加入版本號,下載到的其實也是4.0.3,所以大家在下載的時候把版本號也加上了,具體請見本文的附錄一)。另外,建議大家參與一下官網的這篇文章http://www.toptensoftware.com/Articles/137/Long-Time-No-Post-and-PetaPoco-v5,我也是看完之后才知道我下載的版本不是最新的。說明一下:我下載的時間是2014年4月3日,至於這個日期以后的會不會變化就留給大家去驗證了。
3、 先建立一個類庫並命名(我的叫做Controller),然后先添加一個App.config文件,創建數據庫連接字符串,必須指定為providerName=”System.Data.SqlClient”。把第二步下載到的PetaPoco文件壓縮包解壓后把T4模板以及PetaPoco.cs文件拷貝到你的項目中,項目結構如下圖所示,編輯Database.tt,如果需要自動生成視圖的代碼,需要加上這一句:IncludeViews = true; 保存文件后再Database.tt 文件上點擊右鍵,運行自定義工具(可能會有一個.net版本警告,可以直接無視),就能在Database.tt下生成一個Database.cs 文件了,文件里面是什么內容,大家打開看一下就明白了。
4、 使用SingleOrDefault或者Delete的時候,參數用object和用string調用的是兩個不同的接口,public T SingleOrDefault<T>(object primaryKey)和public T SingleOrDefault<T>(string sql, params object[] args),寫法如下:

[WebMethod(Description = "", MessageName = "QueryOne", EnableSession = true)] public string QueryOne(object strId) { var db = Hyet.Model.DbUtils.GetInstance(); object obj = db.SingleOrDefault<Tbl_WaiterInfo>(strId); return SerializeHelper<Tbl_WaiterInfo>.Serialize(obj); } [WebMethod(Description = "", MessageName = "DeleteReal", EnableSession = true)] public string DeleteReal(object strId) { var db = Hyet.Model.DbUtils.GetInstance(); object obj = db.Delete<Tbl_WaiterInfo>(strId); return obj.ToString(); }
5、 模糊查詢,用like關鍵字的時候需要注意下面的寫法,這里特別感謝博客園網友的指點。

//注意有Like關鍵字用下面這種寫法(寫法1) //sql.Append("WHERE W.WaiterName Like '%" + strKeyword + "%' OR W.Sex Like '%" + strKeyword + "%' OR W.WaiterAccount Like '%" + strKeyword + "%' ", strKeyword); //來自博客園網友James-yu的指點(寫法2) sql.Append("WHERE W.WaiterName Like @0 OR W.Sex Like @0 OR W.WaiterAccount Like @0 ", "%" + strKeyword + "%"); //不要采用下面這種方式,實現不了模糊查詢 //sql.Append("WHERE W.WaiterName Like '%@0%' OR W.Sex Like '%@0%' OR W.WaiterAccount Like '%@0%' ", strKeyword);
6、 執行存儲過程

db.EnableAutoSelect = false; //需要加上這么一句,是否自動添加select子句 //輸入參數 var param0 = new SqlParameter("@strInput1", System.Data.SqlDbType.VarChar, 255); param0.Direction = System.Data.ParameterDirection.Input; param0.Value = strInput1; var param1 = new SqlParameter("@strInput2", System.Data.SqlDbType.NVarChar, 255); param1.Direction = System.Data.ParameterDirection.Input; param1.Value = strInput2; //輸出參數 var param2 = new SqlParameter("@strOutput1", System.Data.SqlDbType.NVarChar, 255); param2.Direction = System.Data.ParameterDirection.Output; param2.Value = DBNull.Value; var param3 = new SqlParameter("@strOutput2", System.Data.SqlDbType.NVarChar, 255); param3.Direction = System.Data.ParameterDirection.Output; param3.Value = DBNull.Value; var sql = PetaPoco.Sql.Builder.Append("exec 存儲過程名稱 @0,@1,@2 output,@3 output", param0, param1, param2, param3); var result = db.Fetch<T>(sql); //根據實際情況替換T string str = param2.Value.ToString(); //返回值 string str = param3.Value.ToString();//返回值
7、 存儲過程代碼示例:

ALTER PROCEDURE [dbo].[proc_ChuChangQiuTong] @strInput1 NVARCHAR(255), @strInput2 NVARCHAR(255), @strOutput1 NVARCHAR(255) OUTPUT, @strOutput2 NVARCHAR(255) OUTPUT AS Declare @SELECT NVARCHAR(1000) ----存放動態生成的SQL語句 BEGIN SET @SELECT = 'SELECT * FROM dbo.Tbl_WaiterInfo WHERE IsDelete=0' EXEC(@SELECT) --這里執行結果是一個數據集 SET @strOutput1 = @strInput1 SET @strOutput2 = @strInput2 SELECT @strOutput1 SELECT @strOutput2 END
8、 A表(T4模板自動生成對應的A類)Join B表(T4模板自動生成對應的B類),返回結果按平常習慣來說它應該是一個數據集DataSet或者DataTable,但是,PetaPoco沒有返回DataSet或者DataTable的,如Fetch<T>返回的是一個List<T>,這時候就會有麻煩了,這個T到底是寫A呢還是寫B呢?不用糾結,馬上告訴你答案:
解決方法1(最為推薦):因為是用T4模板來自動生成數據庫表或者視圖的模型類,所以不建議在自動生成的代碼里面做過多的擴展,否則一重新生成,之前修改的代碼就會被覆蓋掉了。再來看一下,T4模板生成的是partial class(MSDN給出的官方定義是這樣的:分部類型定義允許將類、結構或接口的定義拆分到多個文件中),如下圖所示:
接着上面的話題,首先添加一個新類,使用與T4模板生成的類相同的名字(確保名稱空間也要匹配),聲明為partial class,給任何Join的列添加[ResultColumn]屬性,這里我們決定來partial A,把Join后B的屬性加進來,代碼舉例如下圖所示,
最后的執行代碼是這樣的:var result = db.Fetch<A>(sql);
項目結構如下圖所示:
解決方法2(這中方法我本人沒有試過,待驗證):可以自己寫一個類C,這個類的屬性就是A和B的Join后的所有列,C類示例代碼:

public class C { public string p1 { get;set; } public long p2 { get;set; } …… }
最后的執行代碼:var articles = db.Fetch<C>(sql);
附錄一(從NuGet安裝PetaPoco,參考來自http://landyer.com/archives/138)
VS2010自帶了NuGet,但是版本可能不是最新的(我的就不是)。
首先把NuGet升級到最新版本。
3. 如上圖,這種情況就是需要更新《NuGet Package Manager》。如果沒有出現,則說明H你的《NuGet》已經是最新的了(前提是你是VS2010),直接進入下一章吧。
4. 點擊《更新》,然后按操作進行就ok了。
5. 依次打開《工具》《庫程序包管理器》《程序包管理器控制台》
6. 敲入命令對可用的版本進行查詢get-package –listavailable –allversion –filter petapoco,如圖
7. 我要使用的是petapoco 5.0.1這一個,敲入命令進行安裝install-package petapoco –version 5.0.1,如圖
中間彈出對話框,直接確定,如果之后報錯直接無視就行了。
8. 將當前焦點窗口轉移回控制台。如下圖輸出,表示安裝成功。
9. 上圖中的《acoms》是我當前的項目,安裝的時候默認要有一個打開的項目的Web的桌面的都可以。
10. PetaPoco的安裝結束。
附錄二(有用的幫助文檔)
http://www.toptensoftware.com/petapoco/
http://landyer.com/archives/138
http://www.cnblogs.com/vento/archive/2013/02/09/2909562.html
http://www.cnblogs.com/youring2/archive/2012/06/04/2532130.html
http://www.cnblogs.com/yanxiaodi/archive/2013/03/25/2978606.html
http://www.toptensoftware.com/Articles/74/PetaPoco-Paged-Queries (針對row_number()問題)
附錄三(附上我這邊調試好的代碼片段)

using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.Services; using Hyet.Model; using Common; using PetaPoco; using System.Data.SqlClient; namespace ServicesApi.API { /// <summary> /// Waiter 的摘要說明 /// </summary> [WebService(Namespace = "http://tempuri.org/")] [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)] [System.ComponentModel.ToolboxItem(false)] // 若要允許使用 ASP.NET AJAX 從腳本中調用此 Web 服務,請取消對下行的注釋。 // [System.Web.Script.Services.ScriptService] public class Waiter : System.Web.Services.WebService { [WebMethod(Description = "添加", MessageName = "Insert", EnableSession = true)] public object Insert(string strEntityInfo) { var db = Hyet.Model.DbUtils.GetInstance(); Tbl_WaiterInfo waiterInfo = SerializeHelper<Tbl_WaiterInfo>.Deserialize(strEntityInfo); return db.Insert(waiterInfo); } [WebMethod(Description = "修改", MessageName = "Update", EnableSession = true)] public string Update(string strEntityInfo) { var db = Hyet.Model.DbUtils.GetInstance(); Tbl_WaiterInfo waiterInfo = SerializeHelper<Tbl_WaiterInfo>.Deserialize(strEntityInfo); object obj = db.Update(waiterInfo); return obj.ToString(); } [WebMethod(Description = "真刪", MessageName = "DeleteReal", EnableSession = true)] public string DeleteReal(object strId) { //參數用object和用string調用的是兩個不同的接口,public T SingleOrDefault<T>(object primaryKey)和public T SingleOrDefault<T>(string sql, params object[] args) var db = Hyet.Model.DbUtils.GetInstance(); object obj = db.Delete<Tbl_WaiterInfo>(strId); return obj.ToString(); } [WebMethod(Description = "假刪", MessageName = "DeleteNoReal", EnableSession = true)] public string DeleteNoReal(object strId) { //參數用object和用string調用的是兩個不同的接口,public T SingleOrDefault<T>(object primaryKey)和public T SingleOrDefault<T>(string sql, params object[] args) var db = Hyet.Model.DbUtils.GetInstance(); object entity = db.SingleOrDefault<Tbl_WaiterInfo>(strId); Tbl_WaiterInfo waiterInfo = (Tbl_WaiterInfo)entity; waiterInfo.IsDelete = 1; object obj = db.Update(waiterInfo); return obj.ToString(); } [WebMethod(Description = "獲取單個實體", MessageName = "QueryOne", EnableSession = true)] public string QueryOne(object strId) { //參數用object和用string調用的是兩個不同的接口,public T SingleOrDefault<T>(object primaryKey)和public T SingleOrDefault<T>(string sql, params object[] args) var db = Hyet.Model.DbUtils.GetInstance(); object obj = db.SingleOrDefault<Tbl_WaiterInfo>(strId); return SerializeHelper<Tbl_WaiterInfo>.Serialize(obj); } [WebMethod(Description = "獲取所有實體", MessageName = "QueryAll", EnableSession = true)] public string QueryAll(string strKeyword) { var db = Hyet.Model.DbUtils.GetInstance(); var sql = PetaPoco.Sql.Builder.Append("select * from Tbl_WaiterInfo where IsDelete=0"); //注意有Like關鍵字用下面這種寫法(寫法1) //if (!string.IsNullOrEmpty(strKeyword)) { sql.Append("and WaiterName like '%" + strKeyword + "%'"); } //注意有Like關鍵字只能用下面這種寫法(寫法2) if (!string.IsNullOrEmpty(strKeyword)) { sql.Append("and WaiterName like @0 ", "%" + strKeyword + "%"); } //不要采用下面這種方式,實現不了模糊查詢 //if (!string.IsNullOrEmpty(strKeyword)) { sql.Append("and WaiterName like '%@0%'", strKeyword); } sql.Append("order by WaiterName asc"); object obj = db.Fetch<Tbl_WaiterInfo>(sql); return SerializeHelper<Tbl_WaiterInfo>.Serialize(obj); } [WebMethod(Description = "分頁獲取實體", MessageName = "QueryPage", EnableSession = true)] public string QueryPage(long pageIndex, long pageSize, string strKeyword) { var db = Hyet.Model.DbUtils.GetInstance(); var sql = PetaPoco.Sql.Builder.Append("select * from Tbl_WaiterInfo where IsDelete=0"); //注意有Like關鍵字用下面這種寫法(寫法1) //if (!string.IsNullOrEmpty(strKeyword)) { sql.Append("and WaiterName like '%" + strKeyword + "%'"); } //注意有Like關鍵字只能用下面這種寫法(寫法2) if (!string.IsNullOrEmpty(strKeyword)) { sql.Append("and WaiterName like @0 ", "%" + strKeyword + "%"); } //不要采用下面這種方式,實現不了模糊查詢 //if (!string.IsNullOrEmpty(strKeyword)) { sql.Append("and WaiterName like '%@0%'", strKeyword); } sql.Append("order by WaiterName asc"); object obj = db.Page<Tbl_WaiterInfo>(pageIndex, pageSize, sql); return SerializeHelper<Tbl_WaiterInfo>.Serialize(obj); } [WebMethod(Description = "獲取記錄總數", MessageName = "GetCount", EnableSession = true)] public string GetCount() { var db = Hyet.Model.DbUtils.GetInstance(); object obj = db.ExecuteScalar<long>("select Count(*) from Tbl_WaiterInfo"); return obj.ToString(); } [WebMethod(Description = "判斷是否存在", MessageName = "CheckExist", EnableSession = true)] public string CheckExist(object strId) { var db = Hyet.Model.DbUtils.GetInstance(); object obj = db.Exists<Tbl_WaiterInfo>(strId); return obj.ToString(); } [WebMethod(Description = "執行事務", MessageName = "DoTrans", EnableSession = true)] public string DoTrans(string strEntityInfo1, string strEntityInfo2) { var db = Hyet.Model.DbUtils.GetInstance(); db.BeginTransaction(); try { db.CompleteTransaction(); return "success"; } catch (Exception) { db.AbortTransaction(); return "faild"; } } [WebMethod(Description = "執行存儲過程(只有輸入參數)", MessageName = "ProcInput", EnableSession = true)] public string ProcInput(object strInput) { var db = Hyet.Model.DbUtils.GetInstance(); db.EnableAutoSelect = false; //一定要加上這句 //注意下面這種寫法Input var param1 = new SqlParameter("@strInput1", System.Data.SqlDbType.NVarChar, 255); param1.Direction = System.Data.ParameterDirection.Input; param1.Value = strInput; var sql = PetaPoco.Sql.Builder.Append("exec proc_KeXuanZeRenRen @0", param1); object obj = db.Fetch<Tbl_WaiterInfo>(sql); return SerializeHelper<List<Tbl_WaiterInfo>>.Serialize(obj); } [WebMethod(Description = "執行存儲過程(只有輸出參數)", MessageName = "ProcOutput", EnableSession = true)] public string ProcOutput() { var db = Hyet.Model.DbUtils.GetInstance(); db.EnableAutoSelect = false; //一定要加上這句,是否自動添加select子句 //不要用 var param1 = new SqlParameter() { Direction = ParameterDirection.Output, SqlDbType = SqlDbType.NVarChar, Value = DBNull.Value }; //不要用 var param2 = new SqlParameter() { Direction = ParameterDirection.Output, SqlDbType = SqlDbType.NVarChar, Value = DBNull.Value }; //注意下面這種寫法Output var param1 = new SqlParameter("@strOutput1", System.Data.SqlDbType.NVarChar, 255); param1.Direction = System.Data.ParameterDirection.Output; param1.Value = DBNull.Value; var param2 = new SqlParameter("@strOutput2", System.Data.SqlDbType.NVarChar, 255); param2.Direction = System.Data.ParameterDirection.Output; param2.Value = DBNull.Value; var sql = PetaPoco.Sql.Builder.Append("exec proc_TestOutput @0 output,@1 output", param1, param2); db.Execute(sql); string str1 = param1.Value.ToString(); string str2 = param2.Value.ToString(); return str1; } [WebMethod(Description = "執行存儲過程(輸入輸出參數)", MessageName = "ProcInputOutput", EnableSession = true)] public string ProcInputOutput(object strInput) { var db = Hyet.Model.DbUtils.GetInstance(); db.EnableAutoSelect = false; //一定要加上這句,是否自動添加select子句 //注意下面這種寫法Input var param1 = new SqlParameter("@strInput1", System.Data.SqlDbType.NVarChar, 255); param1.Direction = System.Data.ParameterDirection.Input; param1.Value = strInput; //注意下面這種寫法Output var param2 = new SqlParameter("@strOutput1", System.Data.SqlDbType.NVarChar, 255); param2.Direction = System.Data.ParameterDirection.Output; param2.Value = DBNull.Value; var param3 = new SqlParameter("@strOutput2", System.Data.SqlDbType.NVarChar, 255); param3.Direction = System.Data.ParameterDirection.Output; param3.Value = DBNull.Value; var sql = PetaPoco.Sql.Builder.Append("exec proc_TestInputOutPut @0, @1 output, @2 output", param1, param2, param3); db.Execute(sql); string str1 = param2.Value.ToString(); string str2 = param3.Value.ToString(); return str1; } [WebMethod(Description = "執行存儲過程(輸入輸出參數)", MessageName = "ProcInputOutput2", EnableSession = true)] public string ProcInputOutput2(object strServiceId, object strKeyword, object strWaiterId1, object strWaiterId2, object strWaiterId3, object strWaiterId4, object pageSize, object pageIndex) { var db = Hyet.Model.DbUtils.GetInstance(); db.EnableAutoSelect = false; //一定要加上這句,是否自動添加select子句 //注意下面這種寫法Input var param1 = new SqlParameter("@strServiceId", System.Data.SqlDbType.VarChar, 255); param1.Direction = System.Data.ParameterDirection.Input; param1.Value = strServiceId; var param2 = new SqlParameter("@strKeyword", System.Data.SqlDbType.NVarChar, 255); param2.Direction = System.Data.ParameterDirection.Input; param2.Value = strKeyword; var param3 = new SqlParameter("@strWaiterId1", System.Data.SqlDbType.NVarChar, 255); param3.Direction = System.Data.ParameterDirection.Input; param3.Value = strWaiterId1; var param4 = new SqlParameter("@strWaiterId2", System.Data.SqlDbType.NVarChar, 255); param4.Direction = System.Data.ParameterDirection.Input; param4.Value = strWaiterId2; var param5 = new SqlParameter("@strWaiterId3", System.Data.SqlDbType.NVarChar, 255); param5.Direction = System.Data.ParameterDirection.Input; param5.Value = strWaiterId3; var param6 = new SqlParameter("@strWaiterId4", System.Data.SqlDbType.NVarChar, 255); param6.Direction = System.Data.ParameterDirection.Input; param6.Value = strWaiterId4; var param7 = new SqlParameter("@pageSize", System.Data.SqlDbType.NVarChar, 255); param7.Direction = System.Data.ParameterDirection.Input; param7.Value = pageSize; var param8 = new SqlParameter("@pageIndex", System.Data.SqlDbType.NVarChar, 255); param8.Direction = System.Data.ParameterDirection.Input; param8.Value = pageIndex; //注意下面這種寫法Output var param9 = new SqlParameter("@strOutput1", System.Data.SqlDbType.NVarChar, 255); param9.Direction = System.Data.ParameterDirection.Output; param9.Value = DBNull.Value; var sql = PetaPoco.Sql.Builder.Append("exec proc_ChuChangQiuTong @0,@1,@2,@3,@4,@5,@6,@7,@8 output", param1, param2, param3, param4, param5, param6, param7, param8, param9); var result = db.Fetch<Tbl_WaiterInfo>(sql); string str9 = param9.Value.ToString(); return str9; } [WebMethod(Description = "可選出場球童", MessageName = "SelectChuChangQiuTong", EnableSession = true)] public void SelectChuChangQiuTong(string strKeyword, string strWaiterId1, string strWaiterId2, string strWaiterId3, string strWaiterId4, int pageSize, int pageIndex) { var db = Hyet.Model.DbUtils.GetInstance(); var sql = PetaPoco.Sql.Builder.Append("SELECT * FROM ("); sql.Append("SELECT UniqueID,WaiterName,WaiterAccount,IsDelete,Sex,WorkStautsName,WorkLeaveName FROM dbo.View_WaiterInfo WHERE IsDelete=0 "); sql.Append("AND UniqueID NOT IN (SELECT WaiterInfoID FROM dbo.View_ServiceWaiters WHERE ServiceEnd IS NULL) "); //過濾已經分配設備的球童 sql.Append("AND UniqueID IN (SELECT DutyWaiterID FROM dbo.Tbl_Equipment WHERE DutyWaiterID IS NOT NULL) "); //過濾掉已經選擇的第1\2\3\4個球童 if (!string.IsNullOrEmpty(strWaiterId1)) { sql.Append("AND UniqueID<>'@0' ", strWaiterId1); } if (!string.IsNullOrEmpty(strWaiterId2)) { sql.Append("AND UniqueID<>'@0' ", strWaiterId2); } if (!string.IsNullOrEmpty(strWaiterId3)) { sql.Append("AND UniqueID<>'@0' ", strWaiterId3); } if (!string.IsNullOrEmpty(strWaiterId4)) { sql.Append("AND UniqueID<>'@0' ", strWaiterId4); } sql.Append(") W "); sql.Append("INNER JOIN "); sql.Append("("); sql.Append("SELECT UniqueID AS EquipmentUniqueID,EquipmentName,EquipmentNo,MobileNumber,"); sql.Append("DutyWaiterID,UseStatus FROM dbo.Tbl_Equipment WHERE UseStatus=1 AND IsDelete=0"); sql.Append(") E "); sql.Append("ON W.UniqueID = E.DutyWaiterID "); //模糊查詢 if (!string.IsNullOrEmpty(strKeyword)) { //注意有Like關鍵字用下面這種寫法(寫法1) //sql.Append("WHERE W.WaiterName Like '%" + strKeyword + "%' OR W.Sex Like '%" + strKeyword + "%' OR W.WaiterAccount Like '%" + strKeyword + "%' ", strKeyword); //來自博客園網友James-yu的指點(寫法2) sql.Append("WHERE W.WaiterName Like @0 OR W.Sex Like @0 OR W.WaiterAccount Like @0 ", "%" + strKeyword + "%"); //不要采用下面這種方式,實現不了模糊查詢 //sql.Append("WHERE W.WaiterName Like '%@0%' OR W.Sex Like '%@0%' OR W.WaiterAccount Like '%@0%' ", strKeyword); } //結果排序 sql.Append("ORDER BY W.WaiterAccount ASC"); Page<Tbl_WaiterInfo> page = db.Page<Tbl_WaiterInfo>(pageIndex, pageSize, sql); List<Tbl_WaiterInfo> list = page.Items; string str = db.LastCommand; } } }

using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.IO; using System.Runtime.Serialization.Json; namespace Common { /// <summary> /// XML序列化助手類 /// </summary> public class SerializeHelper<T> { public static string Serialize(object obj) { if (obj == null) return null; using (MemoryStream memoryStream = new MemoryStream()) { DataContractJsonSerializer dataContractJsonSerializer = new DataContractJsonSerializer(obj.GetType()); dataContractJsonSerializer.WriteObject(memoryStream, obj); return Encoding.UTF8.GetString(memoryStream.ToArray()); } } public static T Deserialize(string str) { using (MemoryStream memoryStream = new MemoryStream(Encoding.UTF8.GetBytes(str))) { DataContractJsonSerializer dataContractJsonSerializer = new DataContractJsonSerializer(typeof(T)); return (T)dataContractJsonSerializer.ReadObject(memoryStream); } } } }