


js implements multi-level cascading menu code on web pages_javascript skills
The example in this article describes how to implement multi-level cascading menus on web pages using js. Share it with everyone for your reference. The details are as follows:
This is a cascading menu effect that you often see on web pages. However, this code is implemented by JS. The contents of the cascading menu are saved in a JS array. In order to make the page beautiful, it is also beautified this time. After checking the table borders, the overall look is more harmonious and practical. The multi-level drop-down menu is more practical for web design.
The operation effect is as shown below:
The online demo address is as follows:
http://demo.jb51.net/js/2015/js-table-select-menu-style-codes/
The specific code is as follows:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=gb2312"> <title>多级级联菜单</title> <script type="text/javascript"> var arr2 = new Array(4); arr2["数码设备"] = new Array("数码相机","打印机"); arr2["家用电器"] = new Array("电视机","电冰箱"); arr2["礼品工艺"] = new Array("鲜花","彩带"); function removeinfo(classMenu){//将下拉框各选项清空 for (var i=0; i < classMenu.options.length; i++){ classMenu.options[i]=null; } } function changeMenu(classList,classMenu){ removeinfo(classMenu) for (var i=0; i < classList.length; i++){ classMenu[i]=new Option(classList[i],classList[i]); } } </script> </head> <body style="font-size:12px"> <table width="487" height="333" border="0" align="center" cellpadding="0" cellspacing="0"> <tr> <td align="center" valign="top"><br> <br> <br> <br> <br> <table width="86%" border="0" align="center" cellpadding="2" cellspacing="1" bgcolor="#6699CC"> <form name="form1"> <tr bgcolor="#FFFFFF"> <td height="22" align="right">所属类别:</td> <td height="22" align="left"><select name="类别" id="类别" onChange="changeMenu(arr2[document.form1.类别.options[document.form1.类别.selectedIndex].text],document.form1.分类);"> <option selected>数码设备</option> <option>家用电器</option> <option>礼品工艺</option> </select> <select name="分类" id="分类"> <option>数码相机</option> <option>打印机</option> </select></td> </tr> <tr bgcolor="#FFFFFF"> <td height="22" align="right">商品名称:</td> <td height="22" align="left"><input name="商品名称" type="text" id="商品名称" size="30" maxlength="50"></td> </tr> <tr bgcolor="#FFFFFF"> <td height="22" align="right">会员价:</td> <td height="22" align="left"><input name="会员价" type="text" id="会员价" size="10"></td> </tr> <tr bgcolor="#FFFFFF"> <td height="22" align="right">提供厂商:</td> <td height="22" align="left"><input name="提供厂商" type="text" id="提供厂商" size="30" maxlength="50"></td> </tr> <tr bgcolor="#FFFFFF"> <td height="22" align="right">商品简介:</td> <td height="22" align="left"><textarea name="商品简介" cols="35" rows="4" id="商品简介"></textarea></td> </tr> <tr bgcolor="#FFFFFF"> <td height="22" align="right">商品数量:</td> <td height="22" align="left"><input name="商品数量" type="text" id="商品数量" size="10"></td> </tr> <tr bgcolor="#FFFFFF"> <td height="22" colspan="2" align="center"><input name="add" type="submit" id="add2" value="添 加"> <input type="reset" name="Submit2" value="重 置"></td> </tr> </form> </table></td> </tr> </table> </body> </html>
I hope this article will be helpful to everyone’s JavaScript programming design.

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