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标题: ASP实现IE地址栏参数的判断 [打印本页]

作者: tznktg    时间: 2008-1-31 16:54
标题: ASP实现IE地址栏参数的判断
当地址栏没有参数"id"时:


Request.QueryString["ID"] == null
Convert.ToString(Request.QueryString["ID"]) == null
Chinaz_com

注意这样会出错:

Request.QueryString["ID"].ToString();

当地址栏有参数"id",但没有赋值的时候:

Request.QueryString["ID"] == ""
Request.QueryString["ID"] == String.Empty
Convert.ToString(Request.QueryString["ID"]) == ""
Convert.ToString(Request.QueryString["ID"]) == String.Empty


同时判断二个条件的时候:


if ("" + Request.QueryString["ID"] == "") {...}
if (("" + Request.QueryString["ID"]).Length == 0) {...}




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