//sql_server:

string driver = "com.microsoft.jdbc.sqlserver.sqlserverdriver";
string url = "jdbc:microsoft:sqlserver://localhost:1433;databasename=test";
string user = "sa";
string password = "";

//oracle:

string driver = "oracle.jdbc.driver.oracledriver";
string url = "jdbc:oracle:thin:@localhost:1521:wanchao";
string user = "scott";
string password = "tiger";

//mysql
string driver="com.mysql.jdbc.driver";
string url="jdbc:mysql://localhost:3306/chinabank?useunicode=true&characterencoding=gbk";
string user="root";
string passeord="root";

class.forname(driver);
con = drivermanager.getconnection(url,user,password);