一、分析php发送网网络请求的方法

    对于php发送网络请求，我们最常用的请求就是curl,有时我们也会用到file_get_contents函数发送网络请求，但file_get_contents只能完成一些间单的网络请求，稍复杂的就无法完成，例如文件上传，cookies，验证，表单提交等，用php的curl可以使用URL的语法模拟浏览器来传输数据，因为它是模拟浏览器，因此它同样支持多种协议，FTP, FTPS, HTTP, HTTPS, GOPHER, TELNET, DICT, FILE 以及 LDAP等协议都可以很好的支持，包括一些：HTTPS认证，HTTP POST方法，HTTP PUT方法，FTP上传，keyberos认证，HTTP上传，代理服务器，cookies，用户名/密码认证，下载文件断点续传，上传文件断点续传，http代理服务器管道，甚至它还支持IPv6，scoket5代理服务器，通过http代理服务器上传文件到FTP服务器等等，所以我们在开发中尽量用curl发网络请求，无论是简单还是复杂

    二、file_get_contents发送网络请求示例

    file_get_contents(path,include_path,context,start,max_length)

    php实现网络请求的方法及函数总结 - 图1

    一般用file_get_contents或者fopen, file , readfile等函数读取url的时候 会创建一个$http_response_header变量保存HTTP响应的报头,使用fopen等函数打开的数据流信息可以用stream_get_meta_data获取

    2. $html = file_get_contents('http://www.baidu.com');
    3. print_r($http_response_header);
    4. $fp = fopen('http://www.baidu.com', 'r');
    5. print_r(stream_get_meta_data($fp));
    6. fclose($fp);

    摸拟post请求：

    2. $url = 'http://192.168.1.1/test.php';
    3. $data = array(
    4.     'keyword' => 'test data',
    5. );
    6. $content = http_build_query($data);
    7. $content_length = strlen($content);
    8. $options = array(
    9.     'http' => array(
    10.         'method' => 'POST',
    11.         'header' =>
    12.         "Content-type: application/x-www-form-urlencoded\r\n" .
    13.         "Content-length: $content_length\r\n",
    14.         'content' => $content
    15.     )
    16. );
    17. echo file_get_contents($url, false, stream_context_create($options));

    三、php 用curl发送网络请求

    curl可以支持https认证、http post、ftp上传、代理、cookies、简单口令认证等等功能,使用前需要先在你的PHP环境中安装和启用curl模块，这里有两种写法供大家参考：

    1. <?php
    2. function geturl($url){
    3.         $headerArray =array("Content-type:application/json;","Accept:application/json");
    4.         $ch = curl_init();
    5.         curl_setopt($ch, CURLOPT_URL, $url);
    6.         curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE); 
    7.         curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE); 
    8.         curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    9.         curl_setopt($ch,CURLOPT_HTTPHEADER,$headerArray);
    10.         $output = curl_exec($ch);
    11.         curl_close($ch);
    12.         $output = json_decode($output,true);
    13.         return $output;
    14. }
    17. function posturl($url,$data){
    18.         $data  = json_encode($data);    
    19.         $headerArray =array("Content-type:application/json;charset='utf-8'","Accept:application/json");
    20.         $curl = curl_init();
    21.         curl_setopt($curl, CURLOPT_URL, $url);
    22.         curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, FALSE);
    23.         curl_setopt($curl, CURLOPT_SSL_VERIFYHOST,FALSE);
    24.         curl_setopt($curl, CURLOPT_POST, 1);
    25.         curl_setopt($curl, CURLOPT_POSTFIELDS, $data);
    26.         curl_setopt($curl,CURLOPT_HTTPHEADER,$headerArray);
    27.         curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
    28.         $output = curl_exec($curl);
    29.         curl_close($curl);
    30.         return json_decode($output，true);
    31. }
    34. function puturl($url,$data){
    35.     $data = json_encode($data);
    36.     $ch = curl_init(); //初始化CURL句柄 
    37.     curl_setopt($ch, CURLOPT_URL, $url); //设置请求的URL
    38.     curl_setopt ($ch, CURLOPT_HTTPHEADER, array('Content-type:application/json'));
    39.     curl_setopt($ch, CURLOPT_RETURNTRANSFER,1); //设为TRUE把curl_exec()结果转化为字串，而不是直接输出 
    40.     curl_setopt($ch, CURLOPT_CUSTOMREQUEST,"PUT"); //设置请求方式
    41.     curl_setopt($ch, CURLOPT_POSTFIELDS, $data);//设置提交的字符串
    42.     $output = curl_exec($ch);
    43.     curl_close($ch);
    44.     return json_decode($output,true);
    45. }
    47. function delurl($url,$data){
    48.     $data  = json_encode($data);
    49.     $ch = curl_init();
    50.     curl_setopt ($ch,CURLOPT_URL,$put_url);
    51.     curl_setopt ($ch, CURLOPT_HTTPHEADER, array('Content-type:application/json'));
    52.     curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1);
    53.     curl_setopt ($ch, CURLOPT_CUSTOMREQUEST, "DELETE");   
    54.     curl_setopt($ch, CURLOPT_POSTFIELDS,$data);
    55.     $output = curl_exec($ch);
    56.     curl_close($ch);
    57.     $output = json_decode($output,true);
    58. }
    60. function patchurl($url,$data){
    61.     $data  = json_encode($data);
    62.     $ch = curl_init();
    63.     curl_setopt ($ch,CURLOPT_URL,$url);
    64.     curl_setopt ($ch, CURLOPT_HTTPHEADER, array('Content-type:application/json'));
    65.     curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1);
    66.     curl_setopt ($ch, CURLOPT_CUSTOMREQUEST, "PATCH");  
    67.     curl_setopt($ch, CURLOPT_POSTFIELDS,$data);     //20170611修改接口，用/id的方式传递，直接写在url中了
    68.     $output = curl_exec($ch);
    69.     curl_close($ch);
    70.     $output = json_decode($output);
    71.     return $output;
    72. }
    73. ?>

    一个函数片时各种请求：

    function sendCurl($url, $data = null,$method='POST')
{
    $method=strtoupper($method);
    $start_wdmcurl_time = microtime(true);

    $header = array(' application/x-www-form-urlencoded');
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_FAILONERROR, false);
    // https 请求
    if (strlen($url) > 5 && strtolower(substr($url, 0, 5)) == "https")
    {
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
    }
    if($method=='GET'){
        if($data && is_array($data) && count($data)>0 ){
            $url.="?".http_build_query($data);
        }
        curl_setopt($ch, CURLOPT_URL, $url);
    }elseif($method=='POST'){
        curl_setopt($ch, CURLOPT_POST, 1);
        curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
        if (is_array($data) && count($data)>0)
        {
            curl_setopt($ch, CURLOPT_POST, true);
            $isPostMultipart = false;
            foreach ($data as $k => $v)
            {
                if ('@' == substr($v, 0, 1))
                {
                    $isPostMultipart = true;
                    break;
                }
            }
            unset($k, $v);
            if ($isPostMultipart) {
                curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
            } else {
                curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($data));
            }
        }
    }elseif(in_array($method,['PUT','DELETE','PATCH'])){
        curl_setopt($ch, CURLOPT_CUSTOMREQUEST,$method);
        curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
    }
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($ch,CURLOPT_HTTPHEADER,$header);
    $reponse = curl_exec($ch);
    curl_close($ch);
    return $reponse;
}

    四、使用php composer的扩展guzzlehttp

    composer require guzzlehttp/guzzle

    
$client = new \GuzzleHttp\Client();
$response = $client->request('GET', 'https://api.github.com/repos/guzzle/guzzle');

echo $response->getStatusCode(); // 200
echo $response->getHeaderLine('content-type'); // 'application/json; charset=utf8'
echo $response->getBody(); // '{"id": 1420053, "name": "guzzle", ...}'

// Send an asynchronous request.
$request = new \GuzzleHttp\Psr7\Request('GET', 'http://httpbin.org');
$promise = $client->sendAsync($request)->then(function ($response) {
    echo 'I completed! ' . $response->getBody();
});

$promise->wait();

    日常开发中我们尽量用方法三，自定义用curl处理网络请求，或用composer的guzzlehttp扩展库，有起来也很方便。