数据传输神器cURL《专题》

数据传输神器cURL

    Client URL Library Functions 简称cURL，客户端和服务器数据传输工具，使用URL规则进行交互。一般使用在一下几个方向：

1. 网页资源（编写网页爬出，获取网页信息）
2. webservice数据接口资源（动态获取接口数据，比如天气、号码归属地）
3. FTP服务器里面文件资源（FTP服务器上传或下载）
4. 其它资源（所有网络资源可以通过CURL下载和访问）

    注意：使用cURL是要确保系统php环境支持该库。

 

一、cURL操作步骤

1. 初始化。curl_init();
2. 向服务器发送数据和接受数据。curl_exec();
3. 关闭cURL。curl_close();

二、cURL常见实例

  1.   简单网页爬虫(获取网页信息)

 

//简单网页爬虫，获取网页
$curl = curl_init('http://www.baidu.com');
curl_exec($curl);
curl_close($curl);

 

  2.   抓取网页信息部分替换

    关键设置参数CURLOPT_RETURNTRANSFER，执行之后不打印

//抓取网页并部分替换
$curl = curl_init();
curl_setopt($curl, CURLOPT_URL, 'http://www.baidu.com');
curl_setopt($curl, CURLOPT_RETURNTRANSFER, true); //执行之后不直接打印
$output = curl_exec($curl);
echo str_replace('百度','度娘',$output);

 

  3.   webservice获取天气

   第一种

$data = 'theCityName=北京';
$curlobj = curl_init();	
curl_setopt($curlobj, CURLOPT_URL, "http://www.webxml.com.cn/WebServices/WeatherWebService.asmx/getWeatherbyCityName");  
curl_setopt($curlobj, CURLOPT_HEADER, 0); 
curl_setopt($curlobj, CURLOPT_RETURNTRANSFER, 1);  
curl_setopt($curlobj, CURLOPT_POST, 1);  
curl_setopt($curlobj, CURLOPT_POSTFIELDS, $data);  
curl_setopt($curlobj, CURLOPT_HTTPHEADER, array("application/x-www-form-urlencoded; charset=utf-8", 
	"Content-length: ".strlen($data)
	)); 
$rtn = curl_exec($curlobj);   
if(!curl_errno($curlobj)){
	// $info = curl_getinfo($curlobj); 
	// print_r($info);
	echo $rtn;  
} else {
  echo 'Curl error: ' . curl_error($curlobj);
}
curl_close($curlobj);

   

    第二种方式

$data = sprintf('<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope 
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
xmlns:xsd="http://www.w3.org/2001/XMLSchema" 
xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
  <soap:Body>
    <getWeatherbyCityName xmlns="http://WebXml.com.cn/">
      <theCityName>%s</theCityName>
    </getWeatherbyCityName>
  </soap:Body>
</soap:Envelope>','北京');
$curlobj = curl_init();	
curl_setopt($curlobj, CURLOPT_URL, "http://www.webxml.com.cn/WebServices/WeatherWebService.asmx");  
curl_setopt($curlobj, CURLOPT_POST, 1);  
curl_setopt($curlobj, CURLOPT_HEADER, 0); 
curl_setopt($curlobj, CURLOPT_RETURNTRANSFER, 1);  
curl_setopt($curlobj, CURLOPT_POSTFIELDS, $data);  
curl_setopt($curlobj, CURLOPT_HTTPHEADER, array("Content-Type: application/soap+xml; charset=utf-8", 
	"Content-length: ".strlen($data),
	"SOAPAction:\"http://WebXml.com.cn/getWeatherbyCityName\"")); 
$rtn = curl_exec($curlobj);   
if(!curl_errno($curlobj)){
	$info = curl_getinfo($curlobj); 
	print_r($info);
	echo "RETURN: " . $rtn;  
} else {
  echo 'Curl error: ' . curl_error($curlobj);
}
curl_close($curlobj);

 

  4.   cURL实现登录抓取

 

$data=array('username' => 'promonkey', 
	'password' => '1q2w3e',
	'remember'=>1);
$data='username=[e-mail]&password=1q2w3e&remember=1';
$curlobj = curl_init();			// 初始化
curl_setopt($curlobj, CURLOPT_URL, "http://www.imooc.com/user/login");		// 设置访问网页的URL
curl_setopt($curlobj, CURLOPT_RETURNTRANSFER, true);			// 执行之后不直接打印出来

// Cookie相关设置，这部分设置需要在所有会话开始之前设置
date_default_timezone_set('PRC'); // 使用Cookie时，必须先设置时区
curl_setopt($curlobj, CURLOPT_COOKIESESSION, TRUE); 
curl_setopt($curlobj, CURLOPT_HEADER, 0); 
curl_setopt($curlobj, CURLOPT_FOLLOWLOCATION, 1); // 这样能够让cURL支持页面链接跳转

curl_setopt($curlobj, CURLOPT_POST, 1);  
curl_setopt($curlobj, CURLOPT_POSTFIELDS, $data);  
curl_setopt($curlobj, CURLOPT_HTTPHEADER, array("application/x-www-form-urlencoded; charset=utf-8", 
	"Content-length: ".strlen($data)
	)); 
curl_exec($curlobj);	// 执行
curl_setopt($curlobj, CURLOPT_URL, "http://www.imooc.com/space/index");
curl_setopt($curlobj, CURLOPT_POST, 0);  
curl_setopt($curlobj, CURLOPT_HTTPHEADER, array("Content-type: text/xml"
	)); 
$output=curl_exec($curlobj);	// 执行
curl_close($curlobj);			// 关闭cURL
echo $output;

 

 

  5.   FTP上传

$curlobj = curl_init();	
$localfile = 'ftp01.php';
$fp = fopen($localfile, 'r');

curl_setopt($curlobj, CURLOPT_URL, "ftp://192.168.1.100/ftp01_uploaded.php");  
curl_setopt($curlobj, CURLOPT_HEADER, 0); 
curl_setopt($curlobj, CURLOPT_RETURNTRANSFER, 1);  
curl_setopt($curlobj, CURLOPT_TIMEOUT, 300); // times out after 300s
curl_setopt($curlobj, CURLOPT_USERPWD, "peter.zhou:123456");//FTP用户名：密码

curl_setopt($curlobj, CURLOPT_UPLOAD, 1);
curl_setopt($curlobj, CURLOPT_INFILE, $fp);
curl_setopt($curlobj, CURLOPT_INFILESIZE, filesize($localfile));
$rtn = curl_exec($curlobj);  
fclose($fp); 
if(!curl_errno($curlobj)){
	echo "Uploaded successfully.";  
} else {
  echo 'Curl error: ' . curl_error($curlobj);
}
curl_close($curlobj);

 

 

  6.   FTP下载

$curlobj = curl_init();	
curl_setopt($curlobj, CURLOPT_URL, "ftp://192.168.1.100/downloaddemo.txt");  
curl_setopt($curlobj, CURLOPT_HEADER, 0); 
curl_setopt($curlobj, CURLOPT_RETURNTRANSFER, 1);  
curl_setopt($curlobj, CURLOPT_TIMEOUT, 300); // times out after 300s
curl_setopt($curlobj, CURLOPT_USERPWD, "peter.zhou:123456");//FTP用户名：密码
// Sets up the output file
$outfile = fopen('dest.txt', 'wb');//保存到本地的文件名
curl_setopt($curlobj, CURLOPT_FILE, $outfile);

$rtn = curl_exec($curlobj);  
fclose($outfile); 
if(!curl_errno($curlobj)){
	// $info = curl_getinfo($curlobj); 
	// print_r($info);
	echo "RETURN: " . $rtn;  
} else {
  echo 'Curl error: ' . curl_error($curlobj);
}
curl_close($curlobj);

 

  7.   cURL访问https资源

$curlobj = curl_init();			// 初始化
curl_setopt($curlobj, CURLOPT_URL, "https://ajax.aspnetcdn.com/ajax/jquery.validate/1.12.0/jquery.validate.js");		// 设置访问网页的URL
curl_setopt($curlobj, CURLOPT_RETURNTRANSFER, true);			// 执行之后不直接打印出来

// 设置HTTPS支持
date_default_timezone_set('PRC'); // 使用Cookie时，必须先设置时区
curl_setopt($curlobj, CURLOPT_SSL_VERIFYPEER, 0); // 对认证证书来源的检查从证书中检查SSL加密算法是否存在
curl_setopt($curlobj, CURLOPT_SSL_VERIFYHOST, 2); // 

$output=curl_exec($curlobj);	// 执行
curl_close($curlobj);			// 关闭cURL
echo $output;