最近在钻研前端，写了个日期控件，内涵代码注释，希望能帮助到大家~
1.html代码
<!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title></title> <script src="js/dateJs.js"></script> <!--<script src="js/rili.js"></script>--> <style type="text/css"> * { margin: 0; padding: 0; } body { font-size: 13px; } .calendar { 330px; } .calendar .title { position: relative; 100%; height: 30px; line-height: 30px; background: #17a4eb; } .title div { position: absolute; } .prev { left: 10px; } .now { left: 40%; } .next { right: 10px; } input { height: 30px; 326px; } table { 100%; border-collapse: collapse; } table th { border: 1px solid #ccc; } table td { text-align: center; border: 1px solid #ccc; } .red { background-color: #a1cbdb; } .blue { background-color: #e4e3e3; } </style> </head> <body> <input type="text" id="Dateinput" /> <div class="calendar" id="calender" style="display: none;"> </div> </body> </html>
2.js代码
window.onload = function () { //获取日期 输入框 var oInput = document.getElementById('Dateinput'); //获取日历 var oCalender = document.getElementById('calender'); //获取当前日期 var oDate = new Date(); //获取当年 年 var year = oDate.getFullYear(); //获取当前 月 var month = oDate.getMonth() + 1; //日历框不能重复创建 var flag = false; //日期输入框 获取焦点时 加载日历 oInput.onfocus = function () { showDate(year, month); } //显示日历 function showDate(year, month) { if (false == flag) { //1.日历标题 var oTitle = document.createElement('div'); oTitle.className = 'title'; //1.1日历标题文本 var prevM = 0; var nextM = 0; prevM = month - 1; nextM = month + 1; //当月份为1时 上一个月为12 if (month == 1) { prevM = 12; }//当月份为12时 下一个月为1 else if (month == 12) { nextM = 1; } var titleHtml = ""; titleHtml += '<div class="prev" id="prev"><span>'; titleHtml += prevM + '</span>月</div>'; titleHtml += '<div class="now">'; titleHtml += '<span class="span">'; titleHtml += year; titleHtml += '</span>年'; titleHtml += '<span class="span">' + month; titleHtml += '</span>月</div>'; titleHtml += '<div class="next" id="next"><span>'; titleHtml += nextM + '</span>月</div>'; oTitle.innerHTML = titleHtml; //将日历标题 拼接到日历 oCalender.appendChild(oTitle); //1.2获取日历 表头元素（以便添加事件） var oSpans = oCalender.getElementsByTagName('span'); var prevMonth = oSpans[0]; var nextMonth = oSpans[3]; var nowMonth = oSpans[2]; var nowYear = oSpans[1]; //2.创建星期 表头 var otable = document.createElement('table'); var othead = document.createElement('thead'); var otr = document.createElement('tr'); //2.1表头内容填充 var arr = ['日', '一', '二', '三', '四', '五', '六']; for (var i = 0; i < arr.length; i++) { //创建th var oth = document.createElement('th'); oth.innerHTML = arr[i]; otr.appendChild(oth); } //2.2将表头加入到日历 othead.appendChild(otr); otable.appendChild(othead); oCalender.appendChild(otable); //3.添加 当前日历 全部日期 //3.1.先获得当期月 有多少天 var dayNum = 0; if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8 || month == 10 || month == 12) { dayNum = 31; } else if (month == 4 || month == 6 || month == 9 || month == 11) { dayNum = 30; } else if (month == 2 && isLeapYear(year)) { dayNum = 29; } else { dayNum = 28; } //3.2.创建 6行7列 日期容器 var otbody = document.createElement('tbody'); for (var i = 0; i < 6; i++) { var otr = document.createElement('tr'); for (var j = 0; j < 7; j++) { var otd = document.createElement('td'); otr.appendChild(otd); } otbody.appendChild(otr); } otable.appendChild(otbody); //3.3获得 1号对应的是星期几 //3.3.1.将当月1号赋值给日期变量 oDate.setFullYear(year); //注意 js日期的月份是从0 开始计算 oDate.setMonth(month - 1); oDate.setDate(1); //3.3.2.计算1号在第一行日期容器中的位置，依次给日期容器填充内容 //注意 js中 getDay方法是获取当前日期是星期几 var week = oDate.getDay(); var otds = oCalender.getElementsByTagName('td'); for (var i = 0; i < dayNum; i++) { otds[i + week].innerHTML = i + 1; } //让当前日期显示红色、后面的显示蓝色 showColor(otds); //给左右月份绑定点击事件 monthEvent(); //判断最后一行是否全为空 lastTr(otds); flag = true; document.getElementById('calender').style.display = "block"; } } //判断是否是闰年 function isLeapYear(year) { if (year % 100 == 0 && year % 400 == 0) { return true; } else if (year % 100 != 0 && year % 4 == 0) { return true; } else { return false; } } //判断日期容器最后一行是否有值 function lastTr(otds) { var flag = true; for (var i = 35; i < 42; i++) { if (otds[i].innerHTML != '') { flag = false; } } //全是空的 if (flag) { for (var i = 35; i < 42; i++) { otds[i].style.display = 'none'; } } } //当前日期显示红色、前面的显示灰色 function showColor(otds) { //当前日期 var nowday = new Date().getDate(); var nowyear = new Date().getFullYear(); var nowmonth = new Date().getMonth(); var oCalendar = document.getElementById("calender"); ospans = oCalendar.getElementsByTagName('span'); var contralYear = ospans[1].innerHTML; var contralMonth = ospans[2].innerHTML; var oindex = 0; for (var i = 0; i < otds.length; i++) { if (nowday == otds[i].innerHTML && nowyear == contralYear && nowmonth + 1 == contralMonth) { otds[i].className = 'red'; oindex = i; } } } //给左右月份绑定点击事件 function monthEvent() { var oCalendar = document.getElementById("calender"); var prevDiv = document.getElementById("prev"); var nextDiv = document.getElementById("next"); var prevMonth = prevDiv.getElementsByTagName("span"); var nextMonth = nextDiv.getElementsByTagName("span"); prevDiv.onclick = function () { flag = false; oCalendar.innerHTML = ''; showDate(year, parseInt(prevMonth[0].innerHTML)); } nextDiv.onclick = function () { flag = false; oCalendar.innerHTML = ''; showDate(year, parseInt(nextMonth[0].innerHTML)); } } }