curl 基础例子

只要你编译完的PHP设置了支持 cURL 扩展，你就可以开始使用cURL函数了。使用 cURL 函数的基本思想是先使用 curl_init() 初始化 cURL会话，接着可以通过 curl_setopt() 设置需要的全部选项，然后使用 curl_exec() 来执行会话，当执行完会话后使用 curl_close() 关闭会话。这是一个使用 cURL 函数获取 example.com 主页保存到文件的例子：

Example #1 使用 PHP cURL 模块获取 example.com 的主页

<?php

$ch = curl_init("http://www.example.com/");
$fp = fopen("example_homepage.txt", "w");

curl_setopt($ch, CURLOPT_FILE, $fp);
curl_setopt($ch, CURLOPT_HEADER, 0);

curl_exec($ch);
curl_close($ch);
fclose($fp);
?>

User Contributed Notes

Roberto Braga 01-Apr-2015 06:45
It is important to notice that when using curl to post form data and you use an array for CURLOPT_POSTFIELDS option, the post will be in multipart format

<?php
$params=['name'=>'John', 'surname'=>'Doe', 'age'=>36)
$defaults = array(
CURLOPT_URL => 'http://myremoteservice/',
CURLOPT_POST => true,
CURLOPT_POSTFIELDS => $params,
);
$ch = curl_init();
curl_setopt_array($ch, ($options + $defaults));
?>
This produce the following post header:

--------------------------fd1c4191862e3566
Content-Disposition: form-data; name="name"

Jhon
--------------------------fd1c4191862e3566
Content-Disposition: form-data; name="surnname"

Doe
--------------------------fd1c4191862e3566
Content-Disposition: form-data; name="age"

36
--------------------------fd1c4191862e3566--

Setting CURLOPT_POSTFIELDS as follow produce a standard post header

CURLOPT_POSTFIELDS => http_build_query($params),

Which is:
name=John&surname=Doe&age=36

This caused me 2 days of debug while interacting with a java service which was sensible to this difference, while the equivalent one in php got both format without problem.
Anon 18-Feb-2014 08:16
IMO this example would have been better if it had done a check for curl_error(), in order to advertize the existence of this function to people learning about cURL who try the example but mysteriously get no response back for whatever reason.
Anon 18-Feb-2014 07:25
The example fetches a resource (the homepage of a website) and writes it to the the file represented by $fp.

Judging from comments elsewhere in this chapter, the example given ought to set CURLOPT_RETURNTRANSFER to true prior to setting CURLOPT_FILE.
simon dot riget at gmail dot com 30-Apr-2013 07:23
Using ArangoDB with PHP

Coding with a NoSQL data base like ArangoDB can be made more complicated then need be. A simple solution to code for ArangoDB is to use the REST interface directly.
All you need is a few initialization variables and a small function to ease the typing - and of cause install the php5-curls module...
See ArangoDB REST API documentation for options and request types.

<?php
// Initialize options for REST interface
$adb_url="http://127.0.0.1:8529";
$adb_option_defaults = array(
    CURLOPT_HEADER => false,
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_TIMEOUT => 2
  );

// ArangoDB REST function.
// Connection are created demand and closed by PHP on exit.
function adb_rest($method,$uri,$querry=NULL,$json=NULL,$options=NULL){
  global $adb_url,$adb_handle,$adb_option_defaults;

  // Connect
  if(!isset($adb_handle)) $adb_handle = curl_init();

  echo "DB operation: $method $uri $querry $json\n";

  // Compose querry
  $options = array(
    CURLOPT_URL => $adb_url.$uri."?".$querry,
    CURLOPT_CUSTOMREQUEST => $method, // GET POST PUT PATCH DELETE HEAD OPTIONS
    CURLOPT_POSTFIELDS => $json,
  );
  curl_setopt_array($adb_handle,($options + $adb_option_defaults));

  // send request and wait for responce
  $responce =  json_decode(curl_exec($adb_handle),true);

  echo "Responce from DB: \n";
  print_r($responce);
 
  return($responce);
}
?>

Here's some examples:

<?php
// Create a collection
$responce = adb_rest("POST","/_api/collection","",'{"name" : "test"}');

// Create a document
$responce = adb_rest("POST","/_api/document","collection=test",'{ "hello" : "World" }');

// List documents in a collection
$responce=adb_rest("GET","/_api/document","collection=test");

// Change document
$document_handle=$responce['documents'][0];
$responce=adb_rest("PATCH",$document_handle,"",'{ "hello" : "World of mine" }');

// Show document
$responce=adb_rest("GET",$document_handle);

// Search
$responce=adb_rest("POST","/_api/cursor","",'{
  "query" : "FOR t IN test RETURN t",
  "count" : true,
  "batchSize" : 50
}');

while($responce['hasMore'])
  $responce=adb_rest("PUT","/_api/cursor/".$responce['id']);

// Delete document
$responce=adb_rest("DELETE",$document_handle);

// DB Delete collection
$responce=adb_rest("DELETE","/_api/collection/test");

// to handle errors, add something like this:
if($responce['error']) die ("can't create collection");

?>