C++/CLR写的Data Blocks

简介: 

从Microsoft Enterprise Library 5.0 Data Blocks剥离出的数据库操作方法，重新用C++/clr语言封装的一个模块！

只实现几个简单常用的接口，用于c++/clr项目中。

 

 

写在代码前面：

项目是c++/clr的，所以他只需要c++/clr的代码，他不需要我提供dll方式的功能模块，他只需要.h和.cpp文件；

不想说了，其他事情还是放在心里吧，直接贴代码就好了！

 

 

 项目结构：

 

 实现的接口：

 

代码片段：

public ref class DataBase
    {
    public:
        DataBase(String ^connectionString,DbProviderFactory ^dbProviderFactory)
        {
            if(String::IsNullOrEmpty(connectionString))
                throw gcnew ArgumentException("连接字符串不允许为空");
            if (dbProviderFactory == nullptr) 
                throw gcnew ArgumentNullException("数据库提供类型不允许为空");
            this->m_connectionString=connectionString;
            this->m_dbProviderFactory=dbProviderFactory;
        }
        //连接字符串
        property String ^ConnectionString
        {
            String ^get(){return m_connectionString;}
        }

        virtual int ExecuteNonQuery(DbCommand ^command);
        virtual int ExecuteNonQuery(CommandType commandType,String ^commandText);
        virtual Object ^ExecuteScalar(DbCommand ^command);
        virtual Object ^ExecuteScalar(CommandType commandType,String ^commandText);
        virtual DataSet ^ExecuteDataSet(DbCommand ^command);
        virtual DataSet ^ExecuteDataSet(CommandType commandType,String ^commandText);
        virtual IDataReader ^ExecuteReader(DbCommand ^command);
        virtual IDataReader ^ExecuteReader(CommandType commandType,String ^commandText);
        enum class UpdateBehavior
        {
            /// <summary>
            /// No interference with the DataAdapter's Update command. If Update encounters
            /// an error, the update stops.  Additional rows in the Datatable are uneffected.
            /// </summary>
            Standard,
            /// <summary>
            /// If the DataAdapter's Update command encounters an error, the update will
            /// continue. The Update command will try to update the remaining rows. 
            /// </summary>
            Continue,
            /// <summary>
            /// If the DataAdapter encounters an error, all updated rows will be rolled back.
            /// </summary>
            Transactional  
        };
    private:
         String ^m_connectionString;
         DbProviderFactory ^m_dbProviderFactory;

         DbConnection ^GetNewOpenConnection();
         DbCommand ^CreateCommandByCommandType(CommandType commandType,String ^commandText);
    protected:
        virtual DatabaseConnectionWrapper ^GetWrappedConnection();
        static void PrepareCommand(DbCommand ^command,DbConnection ^connection);
        int DoExecuteNonQuery(DbCommand ^command);
        Object ^DoExecuteScalar(IDbCommand ^command);
        IDataReader ^DoExecuteReader(DbCommand ^command,CommandBehavior cmdBehavior);
        void DoLoadDataSet(DbCommand ^command,DataSet ^dataSet,array<String^> ^tableNames);
        DbDataAdapter ^GetDataAdapter(UpdateBehavior updateBehavior);
        virtual void SetUpRowUpdatedEvent(DbDataAdapter ^adapter) { }

    };

#include "DataBase.h"
using namespace DBManager;


/*返回数据库语句执行所影响的行数:int*/
int DataBase::ExecuteNonQuery(DbCommand ^command)
{
    DatabaseConnectionWrapper ^wrapper=GetWrappedConnection();
    PrepareCommand(command,wrapper->Connection);
    int ret=DoExecuteNonQuery(command);
    delete command;
    delete wrapper;
    return ret;
}
int DataBase::ExecuteNonQuery(CommandType commandType,String ^commandText)
{
    DbCommand ^command = CreateCommandByCommandType(commandType, commandText);
    return ExecuteNonQuery(command);
}
int DataBase::DoExecuteNonQuery(DbCommand ^command)
{
    try{
        int rowsAffected = command->ExecuteNonQuery();
        return rowsAffected;
    }
    catch(Exception ^e)
    {
        throw e;
    }
}

/*返回数据库语句执行结果:Object*/
Object ^DataBase::ExecuteScalar(DbCommand ^command)
{
    DatabaseConnectionWrapper ^wrapper=GetWrappedConnection();
    PrepareCommand(command,wrapper->Connection);
    Object ^ret=DoExecuteScalar(command);
    delete command;
    delete wrapper;
    return ret;
}
Object ^DataBase::ExecuteScalar(CommandType commandType,String ^commandText)
{
    DbCommand ^command = CreateCommandByCommandType(commandType, commandText);
    return ExecuteScalar(command);
}
Object ^DataBase::DoExecuteScalar(IDbCommand ^command)
{
    try{
        Object ^returnValue = command->ExecuteScalar();
        return returnValue;
    }
    catch(Exception ^e)
    {
        throw e;
    }
}

/*返回数据库语句执行结果:DataSet*/
DataSet ^DataBase::ExecuteDataSet(DbCommand ^command)
{
    DataSet ^dataSet = gcnew DataSet();
    dataSet->Locale = System::Globalization::CultureInfo::InvariantCulture;  //获取不依赖于区域性（固定）的 CultureInfo。
    DatabaseConnectionWrapper ^wrapper=GetWrappedConnection();
    PrepareCommand(command,wrapper->Connection);
    DoLoadDataSet(command, dataSet, gcnew array<String^>{"Table"});
    delete wrapper;
    return dataSet;
}
DataSet ^DataBase::ExecuteDataSet(CommandType commandType,String ^commandText)
{
    DbCommand ^command = CreateCommandByCommandType(commandType, commandText);
    return ExecuteDataSet(command);
}
void DataBase::DoLoadDataSet(DbCommand ^command,DataSet ^dataSet,array<String^> ^tableNames)
{
    if (tableNames == nullptr) 
        throw gcnew ArgumentNullException("表名数组不允许为空");
    if (tableNames->Length == 0)
    {
        throw gcnew ArgumentException("表名数组长度为0");
    }
    for (int i = 0; i < tableNames->Length; i++)
    {
        if (String::IsNullOrEmpty(tableNames[i])) 
            throw gcnew ArgumentException(String::Concat("表名数组第[", i, "]项为空"));
    }
    DbDataAdapter ^adapter = GetDataAdapter(UpdateBehavior::Standard);
    ((IDbDataAdapter^)adapter)->SelectCommand = command;
    try
    {
        String ^systemCreatedTableNameRoot = "Table";
        for (int i = 0; i < tableNames->Length; i++)
        {
            String ^systemCreatedTableName = (i == 0)
                ? systemCreatedTableNameRoot
                : systemCreatedTableNameRoot + i; //Table,Table1,Table2

            adapter->TableMappings->Add(systemCreatedTableName, tableNames[i]);
        }
        adapter->Fill(dataSet);
    }
    catch(Exception ^e)
    {
        throw e;
    }
    finally
    {
        delete adapter;
    }
}
DbDataAdapter ^DataBase::GetDataAdapter(UpdateBehavior updateBehavior)
{
    DbDataAdapter ^adapter = m_dbProviderFactory->CreateDataAdapter();

    if (updateBehavior == UpdateBehavior::Continue)
    {
        SetUpRowUpdatedEvent(adapter);  //define in ".h"
    }
    return adapter;
}


/*返回数据库语句执行结果:DataReader*/
IDataReader ^DataBase::ExecuteReader(DbCommand ^command)
{
    DatabaseConnectionWrapper ^wrapper=GetWrappedConnection();
    PrepareCommand(command,wrapper->Connection);
    IDataReader ^realReader = DoExecuteReader(command, CommandBehavior::Default);
    RefCountingDataReader ^reader=gcnew RefCountingDataReader(wrapper, realReader);
    return reader->InnerReader;
}
IDataReader ^DataBase::ExecuteReader(CommandType commandType,String ^commandText)
{
    DbCommand ^command = CreateCommandByCommandType(commandType, commandText);
    return ExecuteReader(command);
}
IDataReader ^DataBase::DoExecuteReader(DbCommand ^command,CommandBehavior cmdBehavior)
{
    try{
        IDataReader ^reader = command->ExecuteReader(cmdBehavior);
        return reader;
    }
    catch(Exception ^e)
    {
        throw e;
    }
}


/*添加DbCommand对象的DbConnection属性*/
void DataBase::PrepareCommand(DbCommand ^command,DbConnection ^connection)
{
    if (command == nullptr) throw gcnew ArgumentNullException("不允许空的DbCommand对象");
    if (connection == nullptr) throw gcnew ArgumentNullException("不允许空的DbConnection对象");
    command->Connection=connection;
}

/*返回一个DatabaseConnectionWrapper对象*/
DatabaseConnectionWrapper ^DataBase::GetWrappedConnection()
{
   return gcnew DatabaseConnectionWrapper(GetNewOpenConnection());
}

/*返回数据库连接对象:DbConnection*/
DbConnection ^DataBase::GetNewOpenConnection()
{
    DbConnection ^connection=nullptr;
    try
    {
        try
        {
            connection=m_dbProviderFactory->CreateConnection();
            connection->ConnectionString=m_connectionString;
            connection->Open();
        }
        catch(Exception ^ex)    
        {
            throw ex;
        }
    }
    catch(Exception ^e)
    {
        if(connection!=nullptr)
            connection->Close();
        throw e;
    }
    return connection;
}

/*返回一个DbCommand对象*/
DbCommand ^DataBase::CreateCommandByCommandType(CommandType commandType,String ^commandText)
{
    DbCommand ^command = m_dbProviderFactory->CreateCommand();
    command->CommandType = commandType;
    command->CommandText = commandText;
    return command;
}

void CallBack(Object ^obj)
    {

            //Sql Server数据库测试
            String ^strConn="Data Source=localhost,8306;Initial Catalog=SensorLeadDB;User ID=sa;Password=HZ.bridge";
            SqlDataBase ^sqlbase=gcnew SqlDataBase(strConn);
            int m_count=sqlbase->SqlExecuteNonQuery("delete  from OriginalDatas where SendTime>'2010-06-15' and Sensorid='1-1-2'");
            Object ^m_obj=sqlbase->SqlExecuteScalar("select Sensorid from Sensor");
            DataSet ^m_set=sqlbase->SqlExecuteDataSet("select * from Sensor");
            SqlDataReader ^m_reader=sqlbase->SqlExecuteReader("select Sensorid,SensorType from Sensor");
            Console::WriteLine("Delete Result:{0}",m_count);
            Console::WriteLine("Select Result:{0}",m_obj);
            int tablesCount=m_set->Tables->Count;
            for (int i=0;i<tablesCount;i++)
            {
                Console::WriteLine("DataSet Result:TableName ={0},RowCount={1}",m_set->Tables[i]->TableName,m_set->Tables[i]->Rows->Count);
            }
            Console::WriteLine("SqlDataReader Result:HasRows={0}",m_reader->HasRows);


            //Access数据库测试
            strConn="Provider=Microsoft.Jet.OLEDB.4.0;Data Source=mydatabase.mdb;";
            GenericDatabase ^gdb=gcnew GenericDatabase(strConn,OleDbFactory::Instance);
            m_count=gdb->ExecuteNonQuery(CommandType::Text,"insert into userinfo(name,pass) values('test','123456')");
            m_obj=gdb->ExecuteScalar(CommandType::Text,"select count(*) from userinfo");
            Console::WriteLine("Delete Result:{0}",m_count);
            Console::WriteLine("Select Result:{0}",m_obj);

            frmShow ^frm=gcnew frmShow(m_set,m_reader);
            frm->ShowDialog();

        
    }
    int main(array<System::String ^> ^args)
    {

        WaitCallback ^call=gcnew WaitCallback(CallBack);
        for (int i=0;i<3;i++)
        {
            ThreadPool::QueueUserWorkItem(call);  //并发测试
        }
        Console::ReadLine();
        return 0;
    }

项目文件下载： /Files/cxwx/DBManager.rar

文件DatabaseConnectionWrapper中如下部分稍作修改

//Dispose

~DatabaseConnectionWrapper()

{

int count = Interlocked::Decrement(refCount); //以原子操作的形式递减指定变量的值并存储结果  返回0 refCount=1

if (count == 0)

{

m_Connection->~DbConnection();

}

} 

                !DatabaseConnectionWrapper()

               {

                    //...

               }