function caItems(f) {  
       var n=f.elements.length;
       for (i=0;i<n; i++) {
           var field=f.elements[i];
           if (field.type == 'checkbox' && field.name.match("delitem")) {
                if (f.chk_selectall.checked) {
                    field.checked=true;
                } else {
                    field.checked=false;
                }
           }

       }
   }


// Basic function to show/hide (toggle) an element - pass in the elment id
    function elementToggle(id) {
        var obj = document.getElementById(id);
        if (obj.style.display == 'none') {
            obj.style.display = '';
        } else {
            obj.style.display = 'none';
        }
    }

// Basic function to show/hide an element - pass in the elment id and option.
// Where option can be: show or hide or toggle
    function elementShowHide(id,option) {
        var obj = document.getElementById(id);
        if (option == 'hide') {
            obj.style.display = 'none';
        } else if (option == 'show') {
            obj.style.display = '';
        } else if (option == 'toggle') {
            elementToggle(id);
        }
    }