Nodejs String Padding Left lpad(count, pad)

Method Source Code

/*****************************************************************************
   STRING HELPERS//from   w  w  w. j ava 2 s .  co  m

   A set of prototype modifiers for the String class that will help out with
   everyday string tasks.

   Author:    Jocko MacGregor
   Version:    0.1b
   Date:       January 20, 2014
 *****************************************************************************/


/*
Left pads a string to a specific size with a specific character.

count = The number of characters in the resulting string.
pad = (optional: default=0) The character to pad the string with.
*/
String.prototype.lpad = function(count, pad) {
   pad = pad || '0';
   str = this + '';
   return str.length >= count ? str : new Array(count - str.length + 1).join(pad) + str;      
};


/*
Left pads a string to a specific size with a specific character.

count = The number of characters in the resulting string.
pad = (optional: default=0) The character to pad the string with.
*/
String.prototype.rpad = function(count, pad) {
   pad = pad || '0';
   str = this + '';
   return str.length >= count ? str : str + new Array(count - str.length + 1).join(pad);      
};

Related

1. lpad(character, count)

   String.prototype.lpad = function(character, count) {
       var ch = character || "0";
       var cnt = count || 2;
       var s = "";
       while (s.length < (cnt - this.length)) { s += ch; }
       s = s.substring(0, cnt-this.length);
       return s+this;
   var iterate = function(collection, iterator) {
   ...
   

2. lpad(character, count)

   String.prototype.lpad = function(character, count) {
     var ch = character || "0";
     var cnt = count || 2;
     var s = "";
     while (s.length < (cnt - this.length)) { s += ch; }
     s = s.substring(0, cnt-this.length);
     return s+this;
   

3. lpad(count, pad)

   String.prototype.lpad = function(count, pad) {
       pad = pad || '0';
       str = this + '';
       return str.length >= count ? str : new Array(count - str.length + 1).join(pad) + str;
   };
   

4. lpad(l)

   String.prototype.lpad = function(l) {
     var s = this;
     while (s.length < l) { s = "0"+s; }
     return s;
   

5. lpad(len, padstr)

   String.prototype.lpad = function(len, padstr) {
     return Array(len + 1 - this.length).join(padstr) + this;
   };
   String.prototype.rpad = function(len, padstr) {
     return this + Array(len + 1 - this.length).join(padstr);
   };
   

6. lpad(len, s)

   String.prototype.lpad = function(len, s) {   
       var a = new Array(this);   
       var n = (len - this.length);   
       for ( var i = 0; i < n; i++) {   
           a.unshift(s);   
       return a.join("");   
   };