var current_element=1;
function addCategory(example_name){
// creating input box
var categoryEl = document.createElement('input');
categoryEl.setAttribute('type', 'text');
categoryEl.setAttribute('id',   'category_'+current_element);
categoryEl.setAttribute('size',   '35');
categoryEl.setAttribute('name', 'category[]');
if(example_name!=''){
categoryEl.setAttribute('value', example_name);
categoryEl.setAttribute('style', 'color:#888');
}
categoryEl.setAttribute('onblur', 'if(this.value==\'\'||this.value==\''+example_name+'\'){this.value=\''+example_name+'\';this.style.color=\'#888\'};;setTimeout(\'document.getElementById(\\\'category_box_'+current_element+'\\\').style.display=\\\'none\\\'\',10);');
categoryEl.setAttribute('onkeydown', 'return displayunicode(event,'+current_element+');');
categoryEl.setAttribute('onclick', 'if(this.value==\'\'||this.value==\''+example_name+'\'){this.value=\'\';this.style.color=\'#000\';}');
categoryEl.setAttribute('onkeyup', 'showUser(this.value,\''+current_element+'\',event);');
// creatin div container
var category_div = document.createElement('div');
category_div.setAttribute('id','cat_'+current_element);
category_div.setAttribute('class','cat_cn');
// creatin a element
var category_a = document.createElement('a');
category_a.setAttribute('href','javascript:removeCategory('+current_element+')');
// appending all elements
category_div.appendChild(categoryEl);
category_a.appendChild(document.createTextNode(' remove'));
category_div.appendChild(category_a);
// appending to all to single element in HTML
document.getElementById('category_cn').appendChild(category_div);
//increment current element
current_element++;
}

function removeCategory(element_id){
var el=document.getElementById('cat_'+element_id);
el.parentNode.removeChild(el);
}