链接数据库类 DB.CS

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;   //自己导入命名空间
/// <summary>
/// DB 的摘要说明
/// </summary>
public class DB
{
 public DB()
 {
  //
  // TODO: 在此处添加构造函数逻辑
  //
 }

//建立链接
    public static SqlConnection createConnection()
    {
        System.Data.SqlClient.SqlConnection con = new SqlConnection("server=localhost;database=login;Uid=sa;Pwd=admin;");
        return con;
    }
}