JavaScript中Date对象的常用方法示例
内容摘要
getFullYear()
使用 getFullYear() 获取年份。
源代码:
</script>
<!DOCTYPE html>
<html>
<body>
​
<p id="demo">Click the button to display the full year o
使用 getFullYear() 获取年份。
源代码:
</script>
<!DOCTYPE html>
<html>
<body>
​
<p id="demo">Click the button to display the full year o
文章正文
getFullYear()
使用 getFullYear() 获取年份。
源代码:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 | </script> <!DOCTYPE html> <html> <body> <p id= "demo" >Click the button to display the full year of todays date .</p> <button onclick= "myFunction()" >Try it</button> <script> function myFunction() { var d = new Date (); var x = document.getElementById( "demo" ); x.innerHTML=d.getFullYear(); } </script> </body> </html> |
测试结果:
1 | 2015 |
getTime()
getTime() 返回从 1970 年 1 月 1 日至今的毫秒数。
源代码:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 | <!DOCTYPE html> <html> <body> <p id= "demo" >Click the button to display the number of milliseconds since midnight, January 1, 1970.</p> <button onclick= "myFunction()" >Try it</button> <script> function myFunction() { var d = new Date (); var x = document.getElementById( "demo" ); x.innerHTML=d.getTime(); } </script> </body> </html> |
测试结果:
1 | 1445669203860 |
setFullYear()
如何使用 setFullYear() 设置具体的日期。
源代码:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 | <!DOCTYPE html> <html> <body> <p id= "demo" >Click the button to display a date after changing the year, month, and day.</p> <button onclick= "myFunction()" >Try it</button> <script> function myFunction() { var d = new Date (); d.setFullYear(2020,10,3); var x = document.getElementById( "demo" ); x.innerHTML=d; } </script> <p>Remember that JavaScript counts months from 0 to 11. Month 10 is November.</p> </body> </html> |
测试结果:
1 | Tue Nov 03 2020 14:47:46 GMT+0800 (中国标准时间) |
toUTCString()
如何使用 toUTCString() 将当日的日期(根据 UTC)转换为字符串。
源代码:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 | <!DOCTYPE html> <html> <body> <p id= "demo" >Click the button to display the UTC date and time as a string.</p> <button onclick= "myFunction()" >Try it</button> <script> function myFunction() { var d = new Date (); var x = document.getElementById( "demo" ); x.innerHTML=d.toUTCString(); } </script> </body> </html> |
测试结果:
1 | Sat, 24 Oct 2015 06:49:05 GMT |
getDay()
如何使用 getDay() 和数组来显示星期,而不仅仅是数字。
源代码:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 | <!DOCTYPE html> <html> <body> <p id= "demo" >Click the button to display todays day of the week.</p> <button onclick= "myFunction()" >Try it</button> <script> function myFunction() { var d = new Date (); var weekday= new Array(7); weekday[0]= "Sunday" ; weekday[1]= "Monday" ; weekday[2]= "Tuesday" ; weekday[3]= "Wednesday" ; weekday[4]= "Thursday" ; weekday[5]= "Friday" ; weekday[6]= "Saturday" ; var x = document.getElementById( "demo" ); x.innerHTML=weekday[d.getDay()]; } </script> </body> </html> |
测试结果:
1 | Saturday |
Display a clock
如何在网页上显示一个钟表。
源代码:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 | <!DOCTYPE html> <html> <head> <script> function startTime() { var today= new Date (); var h=today.getHours(); var m=today.getMinutes(); var s=today.getSeconds(); // add a zero in front of numbers<10 m=checkTime(m); s=checkTime(s); document.getElementById( 'txt' ).innerHTML=h+ ":" +m+ ":" +s; t=setTimeout( function (){startTime()},500); } function checkTime(i) { if (i<10) { i= "0" + i; } return i; } </script> </head> <body onload= "startTime()" > <div id= "txt" ></div> </body> </html> |
代码注释