// JavaScript Document
function showContent(link) {   
  
        var cont = document.getElementById('cent');   
        var loading = document.getElementById('loading');   
  
        cont.innerHTML = loading.innerHTML;   
  
        var http = createRequestObject();   
        if( http )    
        {   
            http.open('post', link);   
            http.onreadystatechange = function ()    
            {   
                if(http.readyState == 4)    
                {   
                    cont.innerHTML = http.responseText;   
                }   
            }   
            http.send(null);       
        }   
        else    
        {   
            document.location = link;   
        }   
    }   
  
    // создание ajax объекта   
    function createRequestObject()    
    {   
        try { return new XMLHttpRequest() }   
        catch(e)    
        {   
            try { return new ActiveXObject('Msxml2.XMLHTTP') }   
            catch(e)    
            {   
                try { return new ActiveXObject('Microsoft.XMLHTTP') }   
                catch(e) { return null; }   
            }   
        }   
    }