$(function() { var availableTags = [ "@gmail.com", "@msn.com", "@hotmail.com", "@aol.com", "@yahoo.com" ]; function split( val ) { return val.split( /@\s*/ ); } function extractLast( term ) { return split( term ).pop(); } $( ".autoemail" ) .bind( "keydown", function( event ) { if ( event.keyCode === $.ui.keyCode.TAB && $( this ).data( "autocomplete" ).menu.active ) { event.preventDefault(); } }) .autocomplete({ minLength: 0, source: function( request, response ) { response( $.ui.autocomplete.filter( availableTags, extractLast( request.term ) ) ); }, focus: function() { return false; }, select: function( event, ui ) { var terms = split( this.value ); terms.pop(); terms.push( ui.item.value ); terms.push( "" ); this.value = terms.join( "" ); return false; } }); });