我正在尝试使用HTML和JavaScript编写日历，允许用户选择给定年份中的任何月份进行查看。我设置了一个HMTL表单，其中有一个下拉列表可以选择月份，输入框可以输入所需的年份。还有按钮编码在月份和年份之间切换，同时显示当前月份。所有这些都有效，我能够让日历显示在当月。
我正在努力解决的问题是，当我点击切换按钮或选择所需的月/年并按下显示按钮时，日历显示会发生变化。我不知道如何让我的日历以它应该的方式工作。
HTML
<!DOCTYPE html>
<html>
<head>
<script src = "CalendarFunction.js"></script>
<link href="Calendartest.css" rel="stylesheet"/>
</head>
<body onLoad = "CreateCalendar()">
<form name = "DateControl" id = "DateControl" onSubmit = "return false;" method = "post">
<!--Select the month and year to be shown -->
<select name = "Month" id = "month" onChange = "ChooseDate()">
<option value="January" id="January">January</option>
<option value="February" id="February">February</option>
<option value="March" id="March">March</option>
<option value="April" id="April">April</option>
<option value="May" id="May">May</option>
<option value="June" id="June">June</option>
<option value="July" id="July" >July</option>
<option value="August" id="August">August</option>
<option value="September" id="September">September</option>
<option value="October" id="October" >October</option>
<option value="November" id="November">November</option>
<option value="December" id="December">December</option>
</select>
<input name = "Year" type = "text" maxlength = "4">
<!-- Show Calendar -->
<input type = "button" name = "create" value = "Show" onClick = "ChooseDate()">
</TD>
</TR>
<!--Toggle between the months of the year -->
<input type = "button" name = "previousYear" value = "<Year" onClick = "PreviousYear()">
<input type = "button" name = "previousMonth" value = "<Month" onClick = "PreviousMonth()">
<input type = "button" name = "current" value = "Current" onClick = "SetDate()">
<input type = "button" name = "nextYear" value = ">Year" onClick = "NextYear()">
<input type = "button" name = "nextMonth" value = ">Month"onClick = "NextMonth()" >
</form>
<div id = "calendar"></div>
</body>
</html>
JS
function SetDate() {
var now = new Date();
var day = now.getDate();
var month = now.getMonth();
var year = now.getFullYear();
this.focusDay = day;
document.DateControl.Month.selectedIndex = month;
document.DateControl.Year.value = year;
displayCalendar(month, year);
}
function isFourDigitYear(year) {
if (year.length != 4) {
alert("Sorry, the year must be four-digits in length.");
document.DateControl.Year.select();
document.DateControl.Year.focus();
} else {
return true;
}
}
function ChooseDate() {
var year = document.DateControl.Year.value;
if (isFourDigitYear(year)) {
var day = 0;
var month = document.DateControl.Month.selectedIndex;
displayCalendar(month, year);
}
}
function PreviousYear() {
var year = document.DateControl.Year.value;
if (isFourDigitYear(year)) {
var day = 0;
var month = document.DateControl.Month.selectedIndex;
year--;
document.DateControl.Year.value = year;
displayCalendar(month, year);
}
}
function PreviousMonth() {
var year = document.DateControl.Year.value;
if (isFourDigitYear(year)) {
var day = 0;
var month = document.DateControl.Month.selectedIndex;
if (month == 0) {
month = 11;
if (year > 1000) {
year--;
document.DateControl.Year.value = year;
}
} else {
month--;
}
document.DateControl.Month.selectedIndex = month;
displayCalendar(month, year);
}
}
function NextMonth() {
var year = document.DateControl.Year.value;
if (isFourDigitYear(year)) {
var day = 0;
var month = document.DateControl.Month.selectedIndex;
if (month == 11) {
month = 0;
year++;
document.DateControl.Year.value = year;
} else {
month++;
}
document.DateControl.Month.selectedIndex = month;
displayCalendar(month, year);
}
}
function NextYear() {
var year = document.DateControl.Year.value;
if (isFourDigitYear(year)) {
var day = 0;
var month = document.DateControl.Month.selectedIndex;
year++;
document.DateControl.Year.value = year;
displayCalendar(month, year);
}
}
function CreateCalendar() {
var htmlContent = "";
var FebNumberOfDays = "";
var counter = 1;
var now = new Date();
var day = now.getDate();
var month = now.getMonth();
var year = now.getFullYear();
var nextMonth = month + 1;
var prevMonth = month - 1;
if (month == 1) {
if ((year % 100 != 0) && (year % 4 == 0) || (year % 400 == 0)) {
FebNumberOfDays = 29;
} else {
FebNumberOfDays = 28;
}
}
var monthNames = ["January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"];
var dayNames = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"];
var dayPerMonth = ["31", "" + FebNumberOfDays + "", "31", "30", "31", "30", "31", "31", "30", "31", "30", "31"];
var nextDate = new Date(nextMonth + ' 1 ,' + year);
var weekdays = nextDate.getDay();
var weekdays2 = weekdays;
var numOfDays = dayPerMonth[month];
while (weekdays > 0) {
htmlContent += "<td class='monthPre'></td>";
weekdays--;
}
while (counter <= numOfDays) {
if (weekdays2 > 6) {
weekdays2 = 0;
htmlContent += "</tr><tr>";
}
if (counter == day) {
htmlContent += "<td class='dayNow'>" + counter + "</td>";
} else {
htmlContent += "<td class='monthNow'>" + counter + "</td>";
}
weekdays2++;
counter++;
}
var calendarBody = "<table class='calendar'> <tr class='monthNow'><th colspan='7'>" +
monthNames[month] + " " + year + "</th></tr>";
calendarBody += "<tr class='dayNames'> <td>Sun</td> <td>Mon</td> <td>Tues</td>" +
"<td>Wed</td> <td>Thurs</td> <td>Fri</td> <td>Sat</td> </tr>";
calendarBody += "<tr>";
calendarBody += htmlContent;
calendarBody += "</tr></table>";
document.getElementById("calendar").innerHTML = calendarBody;
}
CSS
.monthPre{
color: gray;
text-align: center;
}
.monthNow{
color: blue;
text-align: center;
}
.dayNow{
border: 2px solid black;
color: #FF0;
text-align: center;
}
.calendar td{
htmlContent: 2px;
border: 2px solid black;
width: 140px;
height: 140px;
}
.monthNow th{
background-color: #000000;
color: #FFFFFF;
text-align: center;
}
.dayNames{
background: #0FF000;
color: #FFFFFF;
text-align: center;
}