Hi 

please help me to solve this below issue

 i have some atachments that i have to download, its working fine but i am not able to download .txt files and Images, instead of downloading it displaying only, please help 

controller 

 public List<String> GetSelectedAttachments()
    {   
        attLinks.clear();
        if(selectedAttachments.size()>0)
        {
            integer j = selectedAttachments.size();
            String strURL;
            for(integer i=0; i<j; i++)
            {            
                     strURL= 'https://' + ApexPages.currentPage().getHeaders().get('Host') 
                + '/servlet/servlet.FileDownload?file='  + selectedAttachments[i].Id;
                
                 //strURL  = '/servlet/servlet.FileDownload?file='+selectedAttachments[i].Id; 
                attLinks.add(strURL);
                 System.debug('$$$$$$$$$'+attLinks);
            }
            System.debug('&&&&&&&&&&'+attLinks.size());
            return attLinks;
        }
        else
        {
            return null;
        }
    } 

 Visualforce page

<apex:outputPanel id="testin" rendered="{!b}">
<script>
var s='{!SelectedAttachments}';

var myCars=new Array();

var ss=s.substr(1, s.length-2); 

myCars=ss.split(",");

for(var i=0; i< myCars.length; i++)
{

window.open(myCars[i]);
}


</script>
</apex:outputpanel>

Thank you