Reference
网页的动作语言
Examples are better than 1000 words.——一例胜千言
引用
<head></head>
<body></body>
<script></script>
输出
innerHTML
document.write()
window.alert()
console.log()
print()
控制
getElementById("demo")
getElementsByClassName("demo")
getElementsByTagName("p")
querySelectorAll("p.intro")
声明
var
let
cost
注释
//单行注释
/*多行注释*/
运算符
+
-
*
**
/
%
++
--
&&
||
!
==
===
!=
!==
>
<
>=
<=
?
+=
-=
*=
/=
%=
**=
函数
数组:x = ["a","b","c"]
物体:x={name:"fiat",model:"modern",color:"white"}
字符串处理
.length
indexOf()
lastIndexOf()
search()
slice()
substring()
substr()
replace()
toUpperCase()
toLowerCase()
concat()
trim()
charAt()
charCodeAt()
split()
数字
Js语法中,支持数位是15位,以及小数点后17位。
NaN = not a number
isNaN()
数字进制
数字变成物体
toExponential()
toFixed()
toPrecision()
数组
array.foreach()
array.push()
array.pop()
typeof.array
array.join("*")
array.shift()
array.unshift()
delete array[0]
array.splice(2,0,"apple","orange")
array.concat(array)
sort()
reverse()
调用
时间
Date(year, month, day, hours, minutes, seconds, milliseconds)
toUTCString()
toISOString()
toDateString()
getFullYear() | Get the year as a four digit number (yyyy) |
getMonth() | Get the month as a number (0-11) |
getDate() | Get the day as a number (1-31) |
getHours() | Get the hour (0-23) |
getMinutes() | Get the minute (0-59) |
getSeconds() | Get the second (0-59) |
getMilliseconds() | Get the millisecond (0-999) |
getTime() | Get the time (milliseconds since January 1, 1970) |
getDay() | Get the weekday as a number (0-6) |
Date.now() | Get the time. ECMAScript 5. |
Method | Description |
getUTCDate() | Same as getDate(), but returns the UTC date |
getUTCDay() | Same as getDay(), but returns the UTC day |
getUTCFullYear() | Same as getFullYear(), but returns the UTC year |
getUTCHours() | Same as getHours(), but returns the UTC hour |
getUTCMilliseconds() | Same as getMilliseconds(), but returns the UTC milliseconds |
getUTCMinutes() | Same as getMinutes(), but returns the UTC minutes |
getUTCMonth() | Same as getMonth(), but returns the UTC month |
getUTCSeconds() | Same as getSeconds(), but returns the UTC seconds |
Method | Description |
setDate() | Set the day as a number (1-31) |
setFullYear() | Set the year (optionally month and day) |
setHours() | Set the hour (0-23) |
setMilliseconds() | Set the milliseconds (0-999) |
setMinutes() | Set the minutes (0-59) |
setMonth() | Set the month (0-11) |
setSeconds() | Set the seconds (0-59) |
setTime() | Set the time (milliseconds since January 1, 1970) |
数学
Math.PI
Math.round()
Math.pow()
Math.sqrt()
Math.abs()
Math.ceil()
Math.floor()
Math.sin()
Math.cos()
Math.min()
Math.max()
Math.random()
Math.E
Math.SQRT2
Math.SQRT1_2
Math.LN2
Math.LN10
Math.LOG2E
Math.LOG10E
逻辑
逻辑
True or False
Boolean()
variablename = (condition) ? value1:value2
Last updated