//在页面顶部添加脚本if (!Page.ClientScript.IsClientScriptBlockRegistered("myscriptKey"))//判断是否已经存在相同//键值的ScriptBlock{    string myScript = @"function AlertHello(){alert('hello xuanhun!!');}";//脚本内容    Page.ClientScript.RegisterClientScriptBlock(this.GetType(), "myscriptKey", myScript, true);}//在页面底部添加脚本if (!Page.ClientScript.IsStartupScriptRegistered("footscriptkey")){    string CallScript = @"AlertHello();";    Page.ClientScript.RegisterStartupScript(this.GetType(), "footscriptKey", CallScript, true);}// 添加对js文件的引用if (!Page.ClientScript.IsClientScriptIncludeRegistered("incluedeKey")){    string IncludeScript = @"/js/ShowHello.js";    Page.ClientScript.RegisterClientScriptInclude("includeKey", IncludeScript);}