实现一个年、月、季度联动SELECT的javascript代码

<body> <table border=0 height=30px > <tr> <td width=80px> <select onchange="displaySubmenu（this.value）"> <option value="none">请选择报告类型</option> <option value="1,4">月度报告</option> <option value="1,3">季度报告</option> <option value="1,2">半年报告</option> <option value="1">年度报告</option> </select> </td> <td> <select id="submenu_1" name="year" style="display:none;"></select> </td> <td> <select id="submenu_2" name="semiyear" style="display:none;"></select> <select id="submenu_3" name="quarter" style="display:none;"></select> <select id="submenu_4" name="month" style="display:none;"></select> </td> <td> <input id="ok" type="button" onClick="GetValue（）;" value="取值"> </td> </tr> </table> <script> function GetValue（）{ var objlist = document.getElementsByTagName（"SELECT"）; var tmp = new Array（）; var tap = objlist[0].options[objlist[0].selectedIndex].text; strTmp=""; var j = 1; for（var i=1;i<objlist.length;i++）{ if（objlist[i].style.display！="none"）{ strTmp += objlist[i].options[objlist[i].selectedIndex].text + "-"; j++; } } strTmp = strTmp.substring（0,strTmp.length-1）; alert（tap）; alert（strTmp）;} function hideAll（）{ for（i=1;i<5;i++）{ var select = document.getElementById（"submenu_"+i）; while（select.options.length>0）{ select.options.remove（0）; } select.style.display = "none"; } } function initSelect（index）{ var select = document.getElementById（"submenu_"+index）; var now = new Date（）; var currentYear = now.getYear（）; var month = now.getMonth（）; switch（index）{ case 1: for（i=-5;i<=5;i++）{ var value = currentYear+i; var item = new Option（value,value）; select.options.add（item）; } select.selectedIndex = 5; select.style.display = "block"; break; case 2: var semiyears = new Array（"上半年","下半年"）; for（i=0;i<2;i++）{ var item = new Option（semiyears[i],i+1）; select.add（item）; } select.selectedIndex = Math.floor（month/6）; select.style.display = "block"; break; case 3: var quarters = new Array（"一季度","二季度","三季度","四季度"）; for（i=0;i<4;i++）{ var item = new Option（quarters[i],i+1）; select.add（item）; } select.selectedIndex = Math.floor（month/3）; select.style.display = "block"; break; case 4: var months = new Array（"一月","二月","三月","四月","五月","六月","七月","八月","九月","十月","十一月","十二月"）; for（i=0;i<12;i++）{ var item = new Option（months[i],i+1）; select.add（item）; } select.selectedIndex = month; select.style.display = "block"; break; default: break; } } function displaySubmenu（command）{ hideAll（）; if（command ！= "none"）{ var commands = command.split（","）; for（l=0;l<commands.length;l++）{ initSelect（parseInt（commands[l]））; } } } </script> </body>

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