Hello!
I want to send a Static resource image in Email through a controller. the code which i have written for it is given below

Public void sendMail(){
     
Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
         String[] toAddresses = new String[] {info.Location__r.Account__r.Email__c}; 
         mail.setToAddresses(toAddresses);
         mail.setSenderDisplayName('Support');
         mail.setSubject('Invoice');
         mail.setBccSender(false); 
         mail.setUseSignature(false);
         mail.setHtmlBody('<image src="' + StaticResourceURL.GetResourceURL('cpLogo')+ '"/>'); 
          Messaging.sendEmail(new Messaging.SingleEmailMessage[] { mail }); 
         
}

 and the StaticResourcUrl is a class which i have search on net for getting the url of a static resource

public class StaticResourceURL
{
    //Pass the resource name
    public static String GetResourceURL(String resourceName)
    {
        //Fetching the resource
        List<StaticResource> resourceList = [SELECT Name, NamespacePrefix, SystemModStamp FROM StaticResource WHERE Name = :resourceName];
                            
        //Checking if the result is returned or not
        if(resourceList.size() == 1)
        {
           //Getting namespace
           String namespace = resourceList[0].NamespacePrefix;
           //Resource URL
           
           return '/resource/' + resourceList[0].SystemModStamp.getTime() + '/' + (namespace != null && namespace != '' ? namespace + '__' : '') + resourceName; 
        }
        else return '';
    }
    
    public static testMethod void testStaticResourceURL(){
    	StaticResourceURL.GetResourceURL('cpLogo');
    	System.debug(StaticResourceURL.GetResourceURL('cpLogo'));
    }
    
}

but this code is not working for me although system.debug in the class returns /resource/1368709494000/cpLogo ... kindly guide me what is wrong with it