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Detailed tutorial on remote image collection with PHP_PHP tutorial

WBOY
WBOYOriginal
2016-07-13 10:26:30845browse

When we need to collect the content of a certain web page on the Internet, if the pictures on the target website are protected from hotlinking, the pictures we collect directly will not be available on our own website. Then we use a program to download the pictures on the target website to our website server, and then the pictures can be called.

This article will use PHP to implement the remote image collection function. Basic process:
1. Obtain the image address of the target website.
2. Read the image content.
3. Create a path to save the image and name the image.
4. Write the picture content.
5. Complete.
We implement this process by writing several functions.
The function make_dir() creates a directory. Determine whether the image file directory to be saved exists. If it does not exist, create the directory and set the directory to writable permissions.

Copy code The code is as follows:
function make_dir($path){
If(!file_exists($path)){//Create if it does not exist
​​​​ $mk=@mkdir($path,0777); //Permissions
​​​​​@chmod($path,0777);
}
Return true;
}

The function read_filetext() obtains the image content. Use fopen to open the image file, and then fread to read the image file content.
Copy code The code is as follows:

function read_filetext($filepath){
$filepath=trim($filepath);
$htmlfp=@fopen($filepath,"r");
//Remote
If(strstr($filepath,"://")){
​​​​while($data=@fread($htmlfp,500000)){
                 $string.=$data;
          }
}
//Local
else{
           $string=@fread($htmlfp,@filesize($filepath));
}
@fclose($htmlfp);
Return $string;
}

The function write_filetext() writes the file and writes the image content fputs into the file, that is, the image file is saved.
Copy code The code is as follows:

function write_filetext($filepath,$string){
//$string=stripSlashes($string);
$fp=@fopen($filepath,"w");
@fputs($fp,$string);
@fclose($fp);
}

The function get_filename() gets the image name, and you can also customize the file name to be saved.
Copy code The code is as follows:

function get_filename($filepath){
$fr=explode("/",$filepath);
$count=count($fr)-1;
Return $fr[$count];
}

Then combine several functions and call them in the function save_pic(), and finally return the saved picture path.
Copy code The code is as follows:

function save_pic($url,$savepath=''){
//Processing address
$url=trim($url);
$url=str_replace(" ","%20",$url);
//Read file
$string=read_filetext($url);
If(empty($string)){
echo 'Cannot read file';exit;
}
//File name
$filename = get_filename($url);
//Storage directory
Make_dir($savepath); //Create a storage directory
//File address
$filepath = $savepath.$filename;
//Write file
​ write_filetext($filepath,$string);
Return $filepath;
}

The last step is to call the save_pic() function to save the picture. We use the following code for testing.
Copy code The code is as follows:

//Target image address
$pic = "http://img0.pconline.com.cn/pconline/1205/06/2776119_end1_thumb.jpg";
//Save directory
$savepath = "images/";
echo save_pic($pic,$savepath);

In practical applications, we may collect the content of a certain site, such as product information, including collecting anti-hotlink pictures, and save them on the server on the website. At this time, we can use regular matching to match the page content, find all the matching pictures in the page, and then download them to the website server respectively to complete the collection of pictures. The following code is for testing only:
Copy code The code is as follows:

function get_pic($cont,$path){
$pattern_src = '/<[img|IMG].*?src=['|"](.*?(?:[.gif|.jpg]))['|"].*?[/]? >/';
$num = preg_match_all($pattern_src, $cont, $match_src);
$pic_arr = $match_src[1]; //Get the picture array
foreach ($pic_arr as $pic_item) { //Loop to get the address of each picture
           save_pic($pic_item,$path); //Download and save the picture
echo "[OK]..!";
}
}

Then we analyze the page content, find out the main content, and call get_pic() to save the picture.
Copy code The code is as follows:

//We collect pictures from the content page of an article on PConline about mobile phones
$url = "http://gz.pconline.com.cn/321/3215791.html";

$content = file_get_contents($url);//Get web content
$preg = '#
(.*)
#iUs';
preg_match_all($preg, $content, $arr);
$cont = $arr[1][0];
get_pic($cont,'img/');

The above code has been personally tested by the author, and it can collect images, but there are still some scenarios that have not been taken into account. For example, the target website has made more than 302 jumps, and the target website has made various anti-collection methods. It is left to students who like to toss to try it. .

www.bkjia.comtruehttp: //www.bkjia.com/PHPjc/824692.htmlTechArticleWhen we need to collect the content of a web page on the Internet, if the pictures on the target website are protected from hotlinking , the pictures we collected directly are not available on our website. Then...
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