5. <?php
$url=array('新浪'=>'www.sina.com','雅虎'=>'www.yahoo.com','网易'=>'www.163.com','腾讯'=>'www.qq.com','百度'=>'www.baidu.com','新新'=>'xinxin.com');
//键的首字符是新的删除
$ar=preg_grep('#^新.*$#',array_keys($url));
foreach($ar as $v){
unset($url[$v]);
}
print_r($url);
// by funch...
http://hiftp.net
6.
<?php
$array=array(.......);
foreach($array as $key=>$value)
{if(mb_substr($key,0,你知道的键的长度-1,'utf-8')=='你知道的键')
{unset($array[$key]);
}
}