下面是用写的PHP保存远程图片到本地的源程序：

function GrabImage($url,$filename="") {
if($url==""):return false;endif;

if($filename=="") {
$ext=strrchr($url,".");
if($ext!=".gif" && $ext!=".jpg"):return false;endif;
$filename=date("dMYHis").$ext;
}

ob_start();
readfile($url);
$img = ob_get_contents();
ob_end_clean();
$size = strlen($img);

$fp2=@fopen($filename, "a");
fwrite($fp2,$img);
fclose($fp2);

return $filename;
}
$img=GrabImage(http://www.xxx.com/images/_1978837_detector_ap100.jpg,"");
if($img):echo '<pre><img src="'.$img.'"></pre>';else:echo "false";endif;

?>

dedecms中的:

if(!empty($saveremoteimg))
{
$body = stripslashes($body);
$img_array = array();
preg_match_all("/(src|SRC)=[""|'| ]{0,}(http://(.*).(gif|jpg|jpeg|bmp|png))/isU",$body,$img_array);
$img_array = array_unique($img_array[2]);
set_time_limit(0);
$imgUrl = $img_dir."/".strftime("%Y%m%d",time());
$imgPath = $base_dir.$imgUrl;
$milliSecond = strftime("%H%M%S",time());
if(!is_dir($imgPath)) @mkdir($imgPath,0777);
foreach($img_array as $key =>$value)
{
$value = trim($value);
$get_file = @file_get_contents($value);
$rndFileName = $imgPath."/".$milliSecond.$key.".".substr($value,-3,3);
$fileurl = $imgUrl."/".$milliSecond.$key.".".substr($value,-3,3);
if($get_file)
{
$fp = @fopen($rndFileName,"w");
@fwrite($fp,$get_file);
@fclose($fp);
}
$body = ereg_replace($value,$fileurl,$body);
}
$body = addslashes($body);
}