日期:2014-05-16 浏览次数:20431 次
传统的HTML页面中连动下拉框采用了两种方法: 1)直接将下拉框中的内容hardcode于html的javascript中,调用javascript函数循环写入下拉框中。这种方法不适用于下拉框内容经常改变的情况。因为数据源和javascript程序写死在同一页面。 <html> <head> <title>List</title> <meta http-equiv="Content-Type" content="text/html; c harset=gb2312"> <script LANGUAGE="javascript"> <!-- var onecount; onecount=0; subcat = new Array(); subcat[0] = new Array("徐汇区","01","001"); subcat[1] = new Array("嘉定区","01","002"); subcat[2] = new Array("黄浦区","01","003"); subcat[3] = new Array("南昌市","02","004"); subcat[4] = new Array("九江市","02","005"); subcat[5] = new Array("上饶市","02","006"); onecount=6; function changelocation(locationid) { document.myform.smalllocation.length = 0; var locationid=locationid; var i; document.myform.smalllocation.options[0] = new Option('====所有地区====',''); for (i=0;i <onecount; i++) { if (subcat[i][1] == locationid) { document.myform.smalllocation.options[document.myform.smalllocation.length] = new Option(subcat[i][0], subcat[i][2]); } } } //--> </script> </head> <body> <form name="myform" method="post"> <select name="biglocation" onChange="changelocation(document.myform.biglocation.options[document.myform.biglocation.selectedIndex].value)"> <option value="01" selected>上海</option> <option value="02">江西</option> </select> <select name="smalllocation"> <option selected value="">==所有地区==</option> </select> </form> <script LANGUAGE="javascript"> <!-- changelocation(document.myform.biglocation.options[document.myform.biglocation.selectedIndex].value); //--> </script> </body> </html> 2)javascript 直接读取数据库,取数据库中的记录写入javascript中,然后和第一种方法一样,调用javascript函数循环写入下拉框中。此方法将数据源与javascript分开,但,公开数据库的连接,从安全角度说,没有多少实用价值。 我的方法是将下拉框中的数据放在XML文件中,用javascript读XML文件,取得下拉框中的内容。 HTML 文件如下: <!-- myfile.html --> <html> <head> <script language="JavaScript" for="window" event="onload"> var xmlDoc = new ActiveXObject("Microsoft.XMLDOM"); var i=0; var j=0; var subclass_name=""; loadXML(); function loadXML(){ xmlDoc.async="false"; xmlDoc.load("account.xml"); xmlObj=xmlDoc.documentElement; nodes = xmlDoc.documentElement.childNodes; document.frm.mainclass.options.length = 0; document.frm.subclass.options.length = 0; for (i=0;i<xmlObj.childNodes.length;i++){ labels=xmlObj.childNodes(i).getAttribute("display_name"); values=xmlObj.childNodes(i).text; document.frm.mainclass.add(document.createElement("OPTION")); document.frm.mainclass.options[i].text=labels; document.frm.mainclass.options[i].value=values; } } </script> <script language="JavaScript" > var xmlDoc = new ActiveXObject("Microsoft.XMLDOM"); var i=0; var j=0; function setsubclass(main){ var is_selected="N"; if (document.frm.subclass.options.length!=0) { for (i=0;i<=document.frm.subclass.options.length;i++) document.frm.subclass.options[i]=null ; } //重复才有效 if (document.frm.subclass.options.length!=0) { for (i=0;i<=document.frm.subclass.options.length;i++){ document.frm.subclass.options[i]=null ; document.frm.subclass.options.remove(i); } } for (i=0;i<xmlObj.childNodes.length;i++){ var values=""; var lables=""; if (is_selected=="Y") return; labels=xmlObj.childNodes(i).getAttribute("display_name"); values=xmlObj.childNodes(i).text; //alert(labels+ " | "+main); if (labels==main){ is_selected="Y"; for (j=0;j<xmlObj.childNodes(i).childNodes.length;j++){ //subclass_name="document.frm.subclass"; labels=xmlObj.childNodes(i).childNodes(j).getAttribute("display_name"); values=xmlObj.childNodes(i).childNodes(j).text; //alert(values); document.frm.subclass.add(document.createElement("OPTION")); document.frm.subclass.options[j].text=labels; document.frm.subclass.options[j].value=values; } } } } </script> <title>在HTML中调用XML数据</title> </head> <body bgcolor="#FFFFFF"> <FORM NAME="frm"> 类型