asp.net发送电子邮件例子

asp.net发送电子邮件例子:usingSystem;usingSystem.Configuration;usingSystem.Data;usingSystem.Linq;usingSystem.Web;usingSystem.Web.Security;usingSystem.Web.UI;usingSystem.Web.UI.HtmlControls;usingSystem.Web.UI.WebControls;usingSystem.Web.UI.WebControls.WebParts;usingSystem.Xml.Linq;usingSystem.Net;usingSystem.Net.Mail