数据读取类

    今天在听讲座的时候找到了一个比较好的类,赶紧记下来!

    这个类的类图如下,功能还是很丰富的哦!类使用了工厂模式等来扩展功能,非常不错的学习资料!下载地址

    调用这个类也非常简单,第一步是设置连接字符串:

   

< connectionStrings >  
      < clear  />  
      < add name = " PubsData "  connectionString = " Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|PUBS.MDF;Integrated Security=True;User Instance=True "  
        providerName = " System.Data.SqlClient "   />      
      < add name = " ConnectionString2 "  connectionString = " server=(local);uid=sa;pwd=111;database=northwind "  
        providerName = " System.Data.SqlClient "   />  
     < add name = " ConnectionString "  connectionString = " Provider=Microsoft.Jet.OLEDB.4.0; Data Source=C:\\database\\NorthWind.mdb; Persist Security Info=False "  
        providerName = " System.Data.OleDb "   />  
     < add name = " ConnectionString1 "  connectionString = " Data Source=.\SQLEXPRESS;AttachDbFilename=C:\\database\\NorthWind.mdf;Integrated Security=True;User Instance=True "  
        providerName = " System.Data.SqlClient "   />  
     < add name = " ConnectionString3 "  connectionString = " Provider=Microsoft.Jet.OLEDB.4.0;Data Source=c:\\database\\NorthWind.xls;Extended Properties='Excel 8.0;' "  
        providerName = " System.Data.OleDb "   />  
   </ connectionStrings >

    提供了多个数据类型的连接,如果你要用哪个数据库的话,就将其名称改成ConnectionString

    设置完以后就可以轻松完成任何事情了!看下面的示例代码:

   

           DataAccess da  =   new  DataAccess(); 
           DataSet ds  =  da.GetDataSet( " Select * from employees " ); 
           dataGridView1.DataSource  =  ds.Tables[ 0 ].DefaultView;