try
{
//指定要修改的配置文件的路径
Configuration config = System.Web.Configuration.WebConfigurationManager.OpenWebConfiguration("~/");
config.AppSettings.Settings["MailServer"].Value = txtMailServer.Value.Trim();
config.AppSettings.Settings["MailAddress"].Value = txtMailAddress.Value.Trim();
config.AppSettings.Settings["MailUser"].Value = txtMailUser.Value.Trim();
config.AppSettings.Settings["MailPwd"].Value = txtMailPwd.Value.Trim();
config.Save();
//刷新配置节点
ConfigurationManager.RefreshSection("appSettings");
}
catch (Exception)
{
Literal alerts = new Literal();
alerts.Text = "<script>alert('更新配置文件中的邮件服务器参数失败，请确保有足够的权限!');</script>";
Page.Controls.Add(alerts);
}