php抓取网站图片的程序

<?php
/*完成网页内容捕获功能*/
function get_img_url($site_name){
$site_fd = fopen($site_name, "r");
$site_content = "";
while (!feof($site_fd)) {
$site_content .= fread($site_fd, 1024);
}
/*利用正则表达式得到图片链接*/
$reg_tag = '/<img.*?\"([^\"]*(jpg|bmp|jpeg|gif)).*?>/';
$ret = preg_match_all($reg_tag, $site_content, $match_result);
fclose($site_fd);
return $match_result[1];
}

/* 对图片链接进行修正 */
function revise_site($site_list, $base_site){
foreach($site_list as $site_item) {
if (preg_match('/^http/', $site_item)) {
$return_list[] = $site_item;
}else{
$return_list[] = $base_site."/".$site_item;
}
}
return $return_list;
}

/*得到图片名字，并将其保存在指定位置*/
function get_pic_file($pic_url_array, $pos){
$reg_tag = '/.*\/(.*?)$/';
$count = 0;
foreach($pic_url_array as $pic_item){
$ret = preg_match_all($reg_tag,$pic_item,$t_pic_name);
$pic_name = $pos.$t_pic_name[1][0];
$pic_url = $pic_item;
print("Downloading ".$pic_url." ");
$img_read_fd = fopen($pic_url,"r");
$img_write_fd = fopen($pic_name,"w");
$img_content = "";
while(!feof($img_read_fd)){
$img_content .= fread($img_read_fd,1024);

}
fwrite($img_write_fd,$img_content);
fclose($img_read_fd);
fclose($img_write_fd);
print("[OK] ");
}
return 0;
}

function main(){
/* 待抓取图片的网页地址 */
$site_name = "http://image.cn.yahoo.com";
$img_url = get_img_url($site_name);
$img_url_revised = revise_site($img_url, $site_name);
$img_url_unique = array_unique($img_url_revised); //unique array
get_pic_file($img_url_unique,"./");
}

main();
?>