Date object
1.What is a Date object?
The date object can store any date and can be accurate to the milliseconds (1/1000 second).
Syntax: var Udate=new Date();
Note: The initial value is the current time (current computer system time).
2. Common methods of Date objects:
3. Date method example
The code copy is as follows:
var newTime=new Date();//Get the current time
var millSecond=Date.now();//The number of milliseconds converted to the current date
var fullYear=newTime.getFullYear();//Get year
var year=newTime.getYear();//Get year
var month=newTime.getMonth();//Get the month and return 0-11 0 means January 11 means December
var week=newTime.getDay();//Get the number returned from 0-6 on the day of the week, 0 represents Sunday
var today=newTime.getDate();//Get the date of the day
var hours=newTime.getHours();//Get the number of hours
var minutes=newTime.getMinutes();//Get the number of minutes
var seconds=newTime.getSeconds();//Get the number of seconds
console.log(newTime);// Wed Feb 04 2015 10:54:17 GMT+0800 (China Standard Time)
console.log(millSecond);// 1423029309565
console.log(fullYear);// 2015
console.log(year);//115
console.log(month);//1 means February
console.log(week);//3 means Wednesday
console.log(today);//4 No. 4
console.log(hours);//10 hours
console.log(minutes);//54 minutes
console.log(seconds);//17 seconds
Math object
1.What is a Math object ?
Math object, providing mathematical calculations of data.
Note: The Math object is an inherent object. Without creating it, you can call all its properties and methods by directly using Math as an object. This is the difference between it and the Date,String object.
2. Properties and methods of Math objects
Math object properties
Math object method
3. Individual method instance of Math object
1): The ceil() method rounds upwards, and returns an integer greater than or equal to x and closest to x.
The code copy is as follows:
document.write(Math.ceil(0.8) + "<br />")//1
document.write(Math.ceil(6.3) + "<br />")//7
document.write(Math.ceil(5) + "<br />")//5
document.write(Math.ceil(3.5) + "<br />")//4
document.write(Math.ceil(-5.1) + "<br />")//-5
document.write(Math.ceil(-5.9))//-5
2): The floor() method rounds downward, and returns an integer less than or equal to x and closest to x.
The code copy is as follows:
document.write(Math.floor(0.8) + "<br />")//0
document.write(Math.floor(6.3) + "<br />")//6
document.write(Math.floor(5) + "<br />")//5
document.write(Math.floor(3.5) + "<br />")//3
document.write(Math.floor(-5.1) + "<br />")//-6
document.write(Math.floor(-5.9))//-6
3): The round() method can round a number to the closest integer
The code copy is as follows:
document.write(Math.round(0.8) + "<br />")//1
document.write(Math.round(6.3) + "<br />")//6
document.write(Math.round(5) + "<br />")//5
document.write(Math.round(3.5) + "<br />")//4
document.write(Math.round(-5.1) + "<br />")//-5
document.write(Math.round(-5.9)+"<br />")//-6
4): The random() method can return a random number between 0 ~ 1 (greater than or equal to 0 but less than 1).
The code copy is as follows:
document.write(Math.random());//Returns the number between 0 and 1 does not include 1
document.write(Math.random()*10);//Returns the number between 0 and 10 does not include 10
5):min() method: Return the minimum value in a set of numeric values
The code copy is as follows:
document.write(Math.min(2,3,4,6));//2
To get the minimum value in the array, use the apply() method:
The code copy is as follows:
var values=[3,2,1,8,9,7];
document.write(Math.min.apply(Math,values)+"<br>");//1
The Math object is the first parameter to apply, and any array is the second parameter
6):max() method: Return the maximum value in a set of numeric values
The code copy is as follows:
document.write(Math.max(2,3,4,6));//6
To get the minimum value in the array, use the apply() method:
The code copy is as follows:
var values=[3,2,1,8,9,7];
document.write(Math.max.apply(Math,values)+"<br>");//9
The above is all about Date (date object) and Math object in JavaScript. I hope you like it.