SQLHelper的数据库配置：
<connectionStrings>
<!--SqlServerHelper连接字符串设定-->
<add connectionString="server=.;uid=sa;pwd=123456;database=yourdatabase" name="SqlServerHelper"/>
<add name="ApplicationServices"
connectionString="Data Source=...;Initial Catalog=..;User ID=..;Password=.."
providerName="System.Data.SqlClient" />
<!--Oracle连接字符串设定-->
<add connectionString="Data Source=orcl;User Id=system;Password=***;Integrated Security=no" name="OracleHelper"/>
<!--MySql连接字符串设定-->
<add connectionString="server=localhost;uid=root;pwd=123456;database=mysqldatabase" name="MySqlHelper"/>
<!--access连接字符串设定-->
<add connectionString="Provider=Microsoft.Jet.OLEDB.4.0;Data Source=F:\mdbFilePath\db.mdb;Jet OLEDB:Database Password=123" name="MySqlHelper"/>
</connectionStrings>
SQLHelper
原文：http://www.cnblogs.com/Yida-Tingting/p/4565148.html
