PHP cURL详解与实战：从基础用法到自定义类实现

function curl_get($url=''){
    //初始化一个cURL会话
    $ch = curl_init();
    curl_setopt_array($ch, [
        //作用是让curl_exec返回字符串,而不是直接输出
        CURLOPT_RETURNTRANSFER => true,
        CURLOPT_URL => $url
    ]);
    $result = curl_exec($ch);
    curl_close($ch);
    return $result;
}
echo curl_get('http://www.example.com/');

function curl_post($url,$data=[]){
    $ch = curl_init();
    curl_setopt_array($ch,[
        CURLOPT_POST => true,
        CURLOPT_RETURNTRANSFER => true,
        CURLOPT_URL => $url,
        CURLOPT_POSTFIELDS => $data
    ]);
    $result = curl_exec($ch);
    curl_close($ch);
    return $result;
}
 
$post = curl_post('http://httpbin.org/post',['username'=>'vace','age'=>23]);
 
print_r($post);

{
  "form": {
    "age": "23", 
    "username": "vace"
  }, 
  ...
}

function curl_auth($url,$user,$passwd){
    $ch = curl_init();
    curl_setopt_array($ch, [
        CURLOPT_USERPWD => $user.':'.$passwd,
        CURLOPT_URL     => $url,
        CURLOPT_RETURNTRANSFER => true
    ]);
    $result = curl_exec($ch);
    curl_close($ch);
    return $result;
}
 
$authurl = 'http://httpbin.org/basic-auth/vace/passwd';
 
echo curl_auth($authurl,'vace','passwd');

{
  "authenticated": true, 
  "user": "vace"
}

/**
 * [curl_cookies 使用curl发送和保存cookies]
 * @param  string $url       访问URL
 * @param  string $save_path cookies的保存地址
 * @return string            设置cookies后的内容
 */
function curl_cookies($url,$save_path){
    $ch = curl_init();
    curl_setopt_array($ch, [
        CURLOPT_RETURNTRANSFER => true,
        CURLOPT_URL => $url,
        CURLOPT_COOKIEJAR => $save_path,  // 保存Cookie
        CURLOPT_COOKIEFILE => $save_path  // 读取Cookie
    ]);
    $result = curl_exec($ch);
    curl_close($ch);
 
    return $result;
}
echo curl_cookies('http://httpbin.org/cookies/set?cookie1=vace','./cookies.log');

# Netscape HTTP Cookie File
# http://curl.haxx.se/docs/http-cookies.html
# This file was generated by libcurl! Edit at your own risk.
httpbin.org	FALSE	/	FALSE	0	cookie1	vace

/**
 * [curl_download 下载远程文件]
 * @param  string $url      远程地址
 * @param  string $savename 保存本地文件名
 * @return void
 */
function curl_download($url,$savename){
    $fp = fopen($savename, 'w');
    $ch = curl_init($url);
    curl_setopt_array($ch, [
        CURLOPT_FILE => $fp,     // 将输出写入文件
        CURLOPT_HEADER => 0      // 不包含头信息
    ]);
    curl_exec($ch);
    curl_close($ch);
    fclose($fp);
}
 
curl_download('http://httpbin.org/image/png','./down.png');

// 1.GET请求示例
echo Curl::get('http://www.example.com/')->send();
 
// 2.POST请求示例
print_r( Curl::post('http://httpbin.org/post')->setData(['username'=>'vace','age'=>23])->send() );
 
// 3.基本认证示例
echo Curl::get('http://httpbin.org/basic-auth/vace/passwd')->setAuth('vace','passwd')->send();
 
// 4.Cookie操作示例
echo Curl::get('http://httpbin.org/cookies/set?cookie1=vace')->useCookies('./cookies.log')->send();
 
// 5.文件下载示例
Curl::get('http://httpbin.org/image/png')->download('./test.png')->send();

class Curl{
    /**
     * [__callStatic 调用方法请求数据]
     * @param  string $method [allMethod key]
     * @param  array $url    [请求url地址]
     * @return object        [Curl对象]
     */
    public static function __callStatic($method,$url){
        $methods = static::$allMethod;
        if(!array_key_exists($method, $methods)){
            throw new \InvalidArgumentException("Method {$method} not valid HTTP method", 1);    
        }
        return new self($method,$url[0]);
    }
    /**
     * [$allMethod 全部访问方法]
     * @var array
     */
    public static $allMethod = [
        'get'     => false,
        'head'    => false,
        'post'    => true,
        'put'     => true,
        'patch'   => true,
        'delete'  => false,
        'options' => false
    ];
    /**
     * [$url 请求url]
     * @var string
     */
    private $url;
    /**
     * [$method 请求方法]
     * @var string
     */
    private $method;
    /**
     * [$headers curl header]
     * @var array
     */
    private $headers = [];
    /**
     * [$cookies cookies信息]
     * @var array
     */
    private $cookies = [];
    /**
     * [$data 设置数据]
     * @var array
     */
    private $data = [];
 
    /**
     * [$option curl opt 参数]
     * @var array
     */
    private $option = [];
 
    /**
     * [$auth 认证信息]
     * @var mixed
     */
    private $auth = false;
    /**
     * [$ch curl_init 句柄]
     * @var resource
     */
    private $ch;
    
    /**
     * [__construct 构造函数]
     * @param string $method HTTP方法
     * @param string $url    请求URL
     */
    private function __construct($method,$url){
        $this->url = $url;
        $this->method = $method;
    }
 
    // 各种getter/setter方法
    // ...existing code...
 
    /**
     * [send 执行cURL请求]
     * @return mixed 请求结果
     */
    public function send(){
        $this->ch = curl_init();
 
        $strings = [];
        foreach ($this->cookies as $key => $value) {
            $strings[] = "{$key}={$value}";
        }
        if(!empty($strings)) $this->setHeader('cookie',implode(';', $strings));
 
 
        $option = [
            CURLOPT_RETURNTRANSFER => true,
            CURLOPT_HEADER => false,
            CURLOPT_URL => $this->url,
            CURLOPT_HTTPHEADER => $this->headers
        ];
 
        $method = $this->method;
 
        if ($method === 'post') {
            $option[CURLOPT_POST] = true;
        } elseif ($method !== 'get') {
            $option[CURLOPT_CUSTOMREQUEST] = $method;
        }
 
 
        //auth
        if(false !== $this->auth){
            $option[CURLOPT_USERPWD] = $this->auth;
        }
 
        //postdata
        if (static::$allMethod[$method] === true) {
            $option[CURLOPT_POSTFIELDS] = $this->data;
        }
 
        //cookies
        if(false !== $this->cookies_path){
            $option[CURLOPT_COOKIEJAR] = $option[CURLOPT_COOKIEFILE] = $this->cookies_path;
        }
        
        //download
        $filename = $this->download_file;
        if($filename){
            if(!$filename) throw new \Exception("use ->download(filename)", 1);
            $fp = fopen($filename, 'w');
            $option[ CURLOPT_FILE ] = $fp;
        }
 
        //合并配置
        $option = $option + $this->option;
        curl_setopt_array($this->ch,$option);
 
        $result = curl_exec($this->ch);
 
        curl_close($this->ch);
        if($filename){
            fclose($fp);
        }
        return $result;
    }
}