Tips for adding a zero-front JavaScript operator to an instance _ javascript

This article mainly introduces the method of adding zero in front of JavaScript, compares and analyzes the techniques of implementing the zero-padding operation in javascript in the form of examples, and has some reference value, for more information, see the examples in this article. Share it with you for your reference. The details are as follows:

Most of the time, in order to display the format, the first 0 must be performed if a character string is not in the correct position.

1. traditional code

/*** ADD 0 before Operation * @ param number String to be operated * @ param length int destination length */function addZero (number, length) {var buffer = ""; if (number = "") {for (var I = 0; I <length; I ++) {buffer + = "0 ";}} else {if (length <number. length) {return "";} else if (length = number. length) {return number;} else {for (var I = 0; I <(length-number. length); I ++) {buffer + = "0";} buffer + = number ;}} return buffer ;}

2. this code is more concise

Function addZero (str, length) {return new Array (length-str. length + 1). join ("0") + str ;}

I hope this article will help you design javascript programs.