PHP issue in UI

array_key_exists和isset的效率,建议使用后者，代码如下

 
if (!array_key_exists($bl,$tuan_letter_cities)) {                                       
    $tuan_letter_cities[$bl] = array();                                   
} 

对临时变量的使用：

if($name == "www") {
    $letter_cities[$bl][] = array($pcity,
CityUtil::name2domain($pcity), CityUtil::isBigCity($pcity));
} else if ($name == "mall") {
    $letter_cities[$bl][] = array($pcity, 
CityUtil::name2domain($pcity), NewTuan::isYoujuCity($pcity));
    if(NewTuan::isYoujuCity($pcity)){
        if (!array_key_exists($bl,$tuan_letter_cities)) {
             $tuan_letter_cities[$bl] = array();
        }
        $tuan_num++;
        $tuan_letter_cities[$bl][] = array($pcity, CityUtil::name2domain($pcity), true);
    } else {
        if (!array_key_exists($bl, $normal_letter_cities)) {
             $normal_letter_cities[$bl] = array();
        }
        $normal_letter_cities[$bl][]= array($pcity, CityUtil::name2domain($pcity), false);
    }
}