JavaScript built-in date and time formatting time example code

1. Basic knowledge (methods of date objects)

😜 getFullYear() is used to return a 4-digit number representing the year

🤣 getMonth() returns a number representing the month, but the return value is an integer between 0 (January) and 11 (December)

😘 getDate() returns a certain day

😊 getHours() returns the hour field of the time

😍 getMinutes() returns the minutes field of the time

😎 getSeconds() returns the seconds of the time. The return value is an integer between 0 and 59

2. Formatting Dates

Example: Format the current time (because time is passing, the result will be different!)

The code is as follows:

Effect presentation:

3. Encapsulation function to format date (for our later use)

The code is as follows:

Effect presentation:

Although this case is relatively simple, there are still some things that need attention! For example, when we get the month, we must add 1, otherwise the returned month will be 1 less than the actual month. This also reminds us to be careful, careful and careful when typing code!

Attached is a popular js encapsulation function for formatting date and time:

Date.prototype.format = function(fmt){
  var o = {
    "M+" : this.getMonth()+1, //Month "d+" : this.getDate(), //Day "h+" : this.getHours(), //Hours "m+" : this.getMinutes(), //Minutes "s+" : this.getSeconds(), //Seconds "q+" : Math.floor((this.getMonth()+3)/3), //Quarter "S" : this.getMilliseconds() //Milliseconds};

  if(/(y+)/.test(fmt)){
    fmt = fmt.replace(RegExp.$1, (this.getFullYear()+"").substr(4 - RegExp.$1.length));
  }
        
  for(var k in o){
    if(new RegExp("("+ k +")").test(fmt)){
      fmt = fmt.replace(
        RegExp.$1, (RegExp.$1.length==1) ? (o[k]) : (("00"+ o[k]).substr((""+ o[k]).length)));  
    }       
  }

  return fmt;
}

Here’s how to use it:

var now = new Date(); // Usually pass in millisecond timestamp for initialization var nowStr = now.format("yyyy-MM-dd hh:mm:ss");

IV. Conclusion

This concludes this article about JavaScript built-in date and time formatting. For more information about JavaScript built-in time formatting, please search previous articles on 123WORDPRESS.COM or continue browsing the following related articles. I hope you will support 123WORDPRESS.COM in the future!