摘要： 把下面这段代码放在登录用户验证以后：//用户登录验证通过后判断用户是否重复登录 public void SingleUserCheck(string userid) { HttpContext httpContext = System.Web.HttpContext.Current; Hashtable userOnline = (Hashtable)httpContext.Application["Online"]; if (userOnline != null) { ... 阅读全文