本文實例為大家分享了如何利用AOP實現(xiàn)SqlSugar自動事務，供大家參考，具體內(nèi)容如下
先看一下效果,帶接口層的三層架構(gòu):
BL層：
public class StudentBL : IStudentService { private ILogger mLogger; private readonly IStudentDA mStudentDa; private readonly IValueService mValueService; public StudentService(IStudentDA studentDa,IValueService valueService) { mLogger = LogManager.GetCurrentClassLogger(); mStudentDa = studentDa; mValueService = valueService; } [TransactionCallHandler] public IList<Student> GetStudentList(Hashtable paramsHash) { var list = mStudentDa.GetStudents(paramsHash); var value = mValueService.FindAll(); return list; } }假設GetStudentList方法里的mStudentDa.GetStudents和mValueService.FindAll不是查詢操作，而是更新操作，當一個失敗另一個需要回滾，就需要在同一個事務里，當一個出現(xiàn)異常就要回滾事務。
特性TransactionCallHandler就表明當前方法需要開啟事務，并且當出現(xiàn)異常的時候回滾事務,方法執(zhí)行完后提交事務。
DA層：
public class StudentDA : IStudentDA { private SqlSugarClient db; public StudentDA() { db = SugarManager.GetInstance().SqlSugarClient; } public IList<Student> GetStudents(Hashtable paramsHash) { return db.Queryable<Student>().AS("T_Student").With(SqlWith.NoLock).ToList(); } }對SqlSugar做一下包裝
public class SugarManager { private static ConcurrentDictionary<string,SqlClient> _cache = new ConcurrentDictionary<string, SqlClient>(); private static ThreadLocal<string> _threadLocal; private static readonly string _connStr = @"Data Source=localhost;port=3306;Initial Catalog=thy;user id=root;password=xxxxxx;Charset=utf8"; static SugarManager() { _threadLocal = new ThreadLocal<string>(); } private static SqlSugarClient CreatInstance() { SqlSugarClient client = new SqlSugarClient(new ConnectionConfig() { ConnectionString = _connStr, //必填 DbType = DbType.MySql, //必填 IsAutoCloseConnection = true, //默認false InitKeyType = InitKeyType.SystemTable }); var key=Guid.NewGuid().ToString().Replace("-", ""); if (!_cache.ContainsKey(key)) { _cache.TryAdd(key,new SqlClient(client)); _threadLocal.Value = key; return client; } throw new Exception("創(chuàng)建SqlSugarClient失敗"); } public static SqlClient GetInstance() { var id= _threadLocal.Value; if (string.IsNullOrEmpty(id)||!_cache.ContainsKey(id)) return new SqlClient(CreatInstance()); return _cache[id]; } public static void Release() { try { var id = GetId(); if (!_cache.ContainsKey(id)) return; Remove(id); } catch (Exception e) { throw e; } } private static bool Remove(string id) { if (!_cache.ContainsKey(id)) return false; SqlClient client; int index = 0; bool result = false; while (!(result = _cache.TryRemove(id, out client))) { index++; Thread.Sleep(20); if (index > 3) break; } return result; } private static string GetId() { var id = _threadLocal.Value; if (string.IsNullOrEmpty(id)) { throw new Exception("內(nèi)部錯誤: SqlSugarClient已丟失."); } return id; } public static void BeginTran() { var instance=GetInstance(); //開啟事務 if (!instance.IsBeginTran) { instance.SqlSugarClient.Ado.BeginTran(); instance.IsBeginTran = true; } } public static void CommitTran() { var id = GetId(); if (!_cache.ContainsKey(id)) throw new Exception("內(nèi)部錯誤: SqlSugarClient已丟失."); if (_cache[id].TranCount == 0) { _cache[id].SqlSugarClient.Ado.CommitTran(); _cache[id].IsBeginTran = false; } } public static void RollbackTran() { var id = GetId(); if (!_cache.ContainsKey(id)) throw new Exception("內(nèi)部錯誤: SqlSugarClient已丟失."); _cache[id].SqlSugarClient.Ado.RollbackTran(); _cache[id].IsBeginTran = false; _cache[id].TranCount = 0; } public static void TranCountAddOne() { var id = GetId(); if (!_cache.ContainsKey(id)) throw new Exception("內(nèi)部錯誤: SqlSugarClient已丟失."); _cache[id].TranCount++; } public static void TranCountMunisOne() { var id = GetId(); if (!_cache.ContainsKey(id)) throw new Exception("內(nèi)部錯誤: SqlSugarClient已丟失."); _cache[id].TranCount--; } }_cache保存SqlSugar實例，_threadLocal確保同一線程下取出的是同一個SqlSugar實例。
不知道SqlSugar判斷當前實例是否已經(jīng)開啟事務，所以又將SqlSugar包了一層。
public class SqlClient { public SqlSugarClient SqlSugarClient; public bool IsBeginTran = false; public int TranCount = 0; public SqlClient(SqlSugarClient sqlSugarClient) { this.SqlSugarClient = sqlSugarClient; } }IsBeginTran標識當前SqlSugar實例是否已經(jīng)開啟事務，TranCount是一個避免事務嵌套的計數(shù)器。
一開始的例子
[TransactionCallHandler] public IList<Student> GetStudentList(Hashtable paramsHash) { var list = mStudentDa.GetStudents(paramsHash); var value = mValueService.FindAll(); return list; }TransactionCallHandler表明該方法要開啟事務，但是如果mValueService.FindAll也標識了TransactionCallHandler,又要開啟一次事務？所以用TranCount做一個計數(shù)。
使用Castle.DynamicProxy
要實現(xiàn)標識了TransactionCallHandler的方法實現(xiàn)自動事務，使用Castle.DynamicProxy實現(xiàn)BL類的代理
Castle.DynamicProxy一般操作
public class MyClass : IMyClass { public void MyMethod() { Console.WriteLine("My Mehod"); } } public class TestIntercept : IInterceptor { public void Intercept(IInvocation invocation) { Console.WriteLine("before"); invocation.Proceed(); Console.WriteLine("after"); } } var proxyGenerate = new ProxyGenerator(); TestIntercept t=new TestIntercept(); var pg = proxyGenerate.CreateClassProxy<MyClass>(t); pg.MyMethod(); //輸出是 //before //My Mehod //afterbefore就是要開啟事務的地方，after就是提交事務的地方
最后實現(xiàn)
public class TransactionInterceptor : IInterceptor { private readonly ILogger logger; public TransactionInterceptor() { logger = LogManager.GetCurrentClassLogger(); } public void Intercept(IInvocation invocation) { MethodInfo methodInfo = invocation.MethodInvocationTarget; if (methodInfo == null) { methodInfo = invocation.Method; } TransactionCallHandlerAttribute transaction = methodInfo.GetCustomAttributes<TransactionCallHandlerAttribute>(true).FirstOrDefault(); if (transaction != null) { SugarManager.BeginTran(); try { SugarManager.TranCountAddOne(); invocation.Proceed(); SugarManager.TranCountMunisOne(); SugarManager.CommitTran(); } catch (Exception e) { SugarManager.RollbackTran(); logger.Error(e); throw e; } } else { invocation.Proceed(); } } } [AttributeUsage(AttributeTargets.Method, Inherited = true)] public class TransactionCallHandlerAttribute : Attribute { public TransactionCallHandlerAttribute() { } }Autofac與Castle.DynamicProxy結(jié)合使用
創(chuàng)建代理的時候一個BL類就要一次操作
proxyGenerate.CreateClassProxy<MyClass>(t);
而且項目里BL類的實例化是交給IOC容器控制的，我用的是Autofac。當然Autofac和Castle.DynamicProxy是可以結(jié)合使用的
using System.Reflection;using Autofac;using Autofac.Extras.DynamicProxy;using Module = Autofac.Module;public class BusinessModule : Module { protected override void Load(ContainerBuilder builder) { var business = Assembly.Load("FTY.Business"); builder.RegisterAssemblyTypes(business) .AsImplementedInterfaces().InterceptedBy(typeof(TransactionInterceptor)).EnableInterfaceInterceptors(); builder.RegisterType<TransactionInterceptor>(); } }以上就是本文的全部內(nèi)容，希望對大家的學習有所幫助，也希望大家多多支持VEVB武林網(wǎng)。
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