foreach 追加有关问题，求高手帮忙看看

<br />foreach ($citycode as $arr => $value) {<br />$citycode[$arr] = "http://weather.xxx.com/".substr($citycode[$arr], 3,4).".txt";<br />//$citycode[$arr] .= "http://weather.xxx.com/".$citycode[$arr].".txt";<br />}<br />

<br />$citycode[$arr.'1'] = "http://weather.xxx.com/".substr($citycode[$arr], 3,4).".txt";<br />

<br /><?php<br /><br />$citycode = array(<br />	"北京"=>"101010100",<br />	"朝阳"=>"101010300"<br />);<br /><br />$tmp = array();<br /><br />foreach ($citycode as $arr => $value) {<br />	$tmp[] = "http://weather.xxx.com/".substr($value, 3,4).".txt";<br />	$tmp[] = "http://weather.xxx.com/".$value.".txt";<br />}<br /><br />echo implode("\r\n", $tmp);<br /><br />//saveFile('api/weather.txt',implode("\r\n",$citycode));<br />

<br />http://weather.xxx.com/0101.txt<br />http://weather.xxx.com/101010100.txt<br />http://weather.xxx.com/0103.txt<br />http://weather.xxx.com/101010300.txt<br />

<br />$citycode = array(<br />"北京"=>"101010100",<br />"朝阳"=>"101010300"<br />);<br /><br />$result = array();<br /><br />foreach ($citycode as $arr => $value) {<br />    array_push($result,"http://weather.xxx.com/".substr($value, 3,4).".txt");<br />    array_push($result,"http://weather.xxx.com/".$value.".txt");<br />}<br /><br />/*<br /> 功能：按行保存为文件<br />*/<br /><br />saveFile('api/weather.txt',implode("\r\n",$result));<br />