Padding Text in Salesforce / Visualforce

Introduction

Last time I got a request from a client to limit a number to 6 digits and if the number has less than 6 digits, prepend 0 in front of it.

Example: 7007 must become 007007

I had to do this in 

1. Javascript (for display in a disabled textbox) , 
2. Visualforce (for display in a PDF), and 
3. Apex (to send to a Web Service).

Javascript

For the Javascript version, I wrote a small function that would do the left padding of zeroes. This function is called when the page is loaded.

 function addZeroes(eId, size){  
      var elem = document.getElementById(eId)  
      while(elem.value.length < size)  
           elem.value = "0" + elem.value  
 }

The function takes the element Id and size as parameter to limit left padding. In my case the element was an input of type text:

 <input id="agent_number" type="text" value="{!$User.Agent__c}" disabled="true"/>  

The addZeroes() function was called as follows in a <script> tag after the form was loaded.

 <script>  
      addZeroes("agent_number", 6);  
 </script>  

Visualforce

The visualforce solution was hard to find but very simple to implement. I used the formula LPAD.

 {!LPAD($User.Agent_No__c,6,'0')}  

Apex

I could not find a solution that resembles the visualforce LPAD in Apex. I used two methods from the String Class to achieve the same result.

 String agentNum = '7007';  
 String agentNumber = agentNum.leftPad(6).replace(' ', '0');  
 system.debug('## agentNumber : ' + agentNumber);  

leftPad() method is used to pad spaces in front without exceeding the length parameter.
replace() method is used to replace all the spaces with 0.

Thnx & Cheers,
Gulshan.