Use the gd library in php to download all images in the web page, _PHP tutorial

The gd library is used in php to download all the pictures in the web page.

In the early php tutorial, it was mentioned that the php gd library can realize the download of remote pictures, but that is just downloading The principle is the same for a picture. If you want to download all the pictures of a web page, you only need to use regular expressions to judge. Find all the picture URLs and then download them in a loop. I specially wrote the gd library picture download class with reference to network resources. !
The php code is as follows:

<&#63;php
header("Content-type:text/html ; charset=utf-8");
if (!empty($_POST['submit'])){
 $url = $_POST['url'];
 //为了获取相对路径的图片所做的操作
 $url_fields = parse_url($url);
 $main_url = $url_fields['host'];
 $base_url = substr($url,0,strrpos($url, '/')+1);
 //获取网页内容
 //设置代理服务器
 $opts = array('http'=>array('request_fulluri'=>true));
 $context = stream_context_create($opts);
 $content = file_get_contents($url,false,$context);
 //匹配img标签,将所有匹配字符串保存到数组$matches
 $reg = "/<img  src="/static/imghwm/default1.png"  data-src="http://www.bkjia.com/uploads/allimg/150513/222Q559A-0.jpg?201541210942?x-oss-process=image/resize,p_40"  class="lazy" .*&#63;src=\"(.*&#63;)\".*&#63; alt="Use the gd library in php to download all images in the web page, _PHP tutorial" >/i";
 preg_match_all($reg, $content, $matches);
 $count = count($matches[0]);
 for ($i=0; $i<$count; $i++){
 /*将所有图片的url转换为小写
  *$matches[1][$i] = strtolower($matches[1][$i]);
 */
 //如果图片为相对路径就转化为全路径
 if (!strpos('a'.$matches[1][$i], 'http')){
  //因为'/'是第0个位置
  if (strpos('a'.$matches[1][$i], '/')){
  $matches[1][$i] = 'http://'.$main_url.$matches[1][$i];
  }else{
  $matches[1][$i] = $base_url.$matches[1][$i];
  }
 }
 }
 //过滤重复的图片
 $img_arr = array_unique($matches[1]);
 //实例化图片下载类
 $getImg = new DownImage();
 $url_count = count($img_arr);
 for ($i=0; $i<$url_count; $i++){
 $getImg->source = $img_arr[$i];
 $getImg->save_address = './pic/';
 $file = $getImg->download();
 }
 echo "下载完成！哈哈，简单吧！";
}
class DownImage{
 public $source;//远程图片URL
 public $save_address;//保存本地地址
 public $set_extension; //设置图片扩展名
 public $quality; //图片的质量（0~100,100最佳，默认75左右）
 //下载方法（选用GD库图片下载）
 public function download(){
 //获取远程图片信息
 $info = @getimagesize($this->source);
 //获取图片扩展名
 $mime = $info['mime'];
 $type = substr(strrchr($mime, '/'), 1);
 //不同的图片类型选择不同的图片生成和保存函数
 switch($type){
  case 'jpeg':
  $img_create_func = 'imagecreatefromjpeg';
  $img_save_func = 'imagejpeg';
  $new_img_ext = 'jpg';
  $image_quality = isset($this->quality) &#63; $this->quality : 100;
  break;
  case 'png':
  $img_create_func = 'imagecreatefrompng';
  $img_save_func = 'imagepng';
  $new_img_ext = 'png';
  break;
  case 'bmp':
  $img_create_func = 'imagecreatefrombmp';
  $img_save_func = 'imagebmp';
  $new_img_ext = 'bmp';
  break;
  case 'gif':
  $img_create_func = 'imagecreatefromgif';
  $img_save_func = 'imagegif';
  $new_img_ext = 'gif';
  break;
  case 'vnd.wap.wbmp':
  $img_create_func = 'imagecreatefromwbmp';
  $img_save_func = 'imagewbmp';
  $new_img_ext = 'bmp';
  break;
  case 'xbm':
  $img_create_func = 'imagecreatefromxbm';
  $img_save_func = 'imagexbm';
  $new_img_ext = 'xbm';
  break;
  default:
  $img_create_func = 'imagecreatefromjpeg';
  $img_save_func = 'imagejpeg';
  $new_img_ext = 'jpg';
 }
 //根据是否设置扩展名来合成本地文件名
 if (isset($this->set_extension)){
  $ext = strrchr($this->source,".");
  $strlen = strlen($ext);
  $newname = basename(substr($this->source,0,-$strlen)).'.'.$new_img_ext;
 }else{
  $newname = basename($this->source);
 }
 
 //生成本地文件路径
 $save_address = $this->save_address.$newname;
 $img = @$img_create_func($this->source);
 if (isset($image_quality)){
  $save_img = @$img_save_func($img,$save_address,$image_quality);
 }else{
  $save_img = @$img_save_func($img,$save_address);
 }
 return $save_img; 
 }
}
&#63;>
<form method="POST" action="">
远程url地址：<input type="text" name="url" size=30 />
<input type="submit" name="submit" value="下载该页面所有图片" />
</form>

The running results are as shown below:

http://www.bkjia.com/PHPjc/998564.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/998564.htmlTechArticleThe gd library is used in php to download all the images in the web page. In the previous php tutorial, it was mentioned that the php gd library can Realize the download of remote pictures, but it only downloads one picture. The principle is the same...