Detailed explanation of the usage of PHP extension CURL

Detailed explanation of the usage of PHP extension CURL_PHP tutorial

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Release： 2016-07-13 10:24:30

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Function implemented:

1. Realize remote acquisition and collection of content

2. Implement FTP upload and download of PHP web version

3. Implement simulated login: go to an email system, curl can simulate cookies

4. Implement interface docking (API), data transmission, etc.: send text messages through a platform, capture and transmit the transmitted information.

5. Implement simulated cookies, etc.: Some attributes can only be operated when logged in.

How to use the CURL function :

By default, PHP does not support CURL, you need to enable this function in php.ini

;Remove the semicolon in front of extension=php_curl.dll

1 The first step in the entire operation process is to initialize with the cur_init() function

$curl = curl_init(‘www.jb51.net')

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2. Use curl_setopt() function to set options.

3. After setting, execute the transaction curl_exec($curl);

4 Finally close curl_close();

Use PHP CURL to implement transmission and acquisition functions (post transmission method): obtain remote web page data

$user = "admin";
$pass = "admin";
$curlPost = "user=$user&pass=$pass";
$ch = curl_init(); //初始化一个CURL对象
curl_setopt($ch, CURLOPT_URL, "http://localhost/edu/login.php");
//设置你所需要抓取的URL
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 0);
//设置curl参数，要求结果是否输出到屏幕上，为true的时候是不返回到网页中
假设上面的0换成1的话，那么接下来的$data就需要echo一下。
curl_setopt($ch, CURLOPT_POST, 1);
//post提交
curl_setopt($ch, CURLOPT_POSTFIELDS, $curlPost);
$data = curl_exec($ch);
//运行curl,请求网页。
curl_close($ch);
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The most basic part of realizing remote simulated login.

curl still needs to configure the username and password, but it is hidden by the browser.

================================================== =============================

curl simulated login

Simulated login: You can still view the corresponding information even without logging into the php100 forum.

Analyze login fields--->Keep cookies after logging in-->Read cookies and jump to relevant pages--->Crawling count

1. Create a file to save the cookie content after simulating login

2. Simulate user login status by reading the generated cookie content

3. Go to relevant pages to get the content you need

tempname creates a temporary file

The tempnam() function creates a temporary file with a unique file name. If successful, the function returns the new temporary file name. On failure, returns false.

tempnam(dir,prefix)

Parameter Description

dir required. Specifies the directory where temporary files are created.

prefix required. Specifies the beginning of the file name.

Equivalent to, fopen  fwirte  fclose

It can return a boolean value. It is very dangerous to use a third party to log in to your QQ and msn, because it can record your login status and capture your username and password.

Use CURL to simulate logging in to the PHP100 forum

1. Analyze the field names and number of required fields in the input box required for login

2. Save cookies and obtain the number of member gold coins after simulating login

Code:

//初始化一个 cURL 对象
$curl = curl_init();
//设置你需要抓取的URL
curl_setopt($curl, CURLOPT_URL, " http://www.baidu.com ");
//设置cURL 参数，要求结果保存到字符串中还是输出到屏幕上。
curl_setopt($curl, CURLOPT_RETURNTRANSFER, 0);
//运行cURL，请求网页
$data = curl_exec($curl);
//关闭URL请求
curl_close($curl);
$user = "admin";
$pass = "admin100";
$curlPost = "user=$user&pass=$pass";
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, " http://localhost/curl/login.php ");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 0);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS, $curlPost);
$data = curl_exec($ch);
curl_close($ch);
&#63;>
if($_POST['user']=="admin"){
 echo "";
}else{
 echo "";
}
//print_r($_POST);
&#63;>

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