Summary of several ways to open a URL address in PHP

1: get the contents with file_get_contents

 
<?php 
$url='http://www.baidu.com/'; 
$html = file_get_contents($url); 
//print_r($http_response_header); 
ec($html); 
printhr(); 
printarr($http_response_header); 
printhr(); 
?> 

Example code 2: open the url with fopen and get the content

 
<? 
$fp = fopen($url, 'r'); 
printarr(stream_get_meta_data($fp)); 
printhr(); 
while(!feof($fp)) { 
$result .= fgets($fp, 1024); 
} 
echo "url body: $result"; 
printhr(); 
fclose($fp); 
?> 

Example code 3: get the url by post using the file_get_contents function

 
<?php 
$data = array ('foo' => 'bar'); 
$data = http_build_query($data); 
$opts = array ( 
'http' => array ( 
'method' => 'POST', 
'header'=> "Content-type: application/x-www-form-urlencoded" . 
"Content-Length: " . strlen($data) . "", 
'content' => $data 
), 
); 
$context = stream_context_create($opts); 
$html = file_get_contents('http://localhost/e/admin/test.html', false, $context); 
echo $html; 
?> 

Example code 4: open the url with the fsockopen function and get the complete data, including the header and body

 
<? 
function get_url ($url,$cookie=false) { 
$url = parse_url($url); 
$query = $url[path]."?".$url[query]; 
ec("Query:".$query); 
$fp = fsockopen( $url[host], $url[port]?$url[port]:80 , $errno, $errstr, 30); 
if (!$fp) { 
return false; 
} else { 
$request = "GET $query HTTP/1.1"; 
$request .= "Host: $url[host]"; 
$request .= "Connection: Close"; 
if($cookie) $request.="Cookie: $cookien"; 
$request.=""; 
fwrite($fp,$request); 
while(!@feof($fp)) { 
$result .= @fgets($fp, 1024); 
} 
fclose($fp); 
return $result; 
} 
} 
//Get the HTML part of the url, remove the header
function GetUrlHTML($url,$cookie=false) { 
$rowdata = get_url($url,$cookie); 
if($rowdata) 
{ 
$body= stristr($rowdata,""); 
$body=substr($body,4,strlen($body)); 
return $body; 
} 
return false; 
} 

?> 

Example code 5: open the url with the fsockopen function and get the complete data, including the header and body, as a POST

 
<? 
function HTTP_Post($URL,$data,$cookie, $referrer="") { 
// parsing the given URL 
$URL_Info=parse_url($URL); 
// Building referrer 
if($referrer=="") // if not given use this script as referrer 
$referrer="111"; 
// making string from $data 
foreach($data as $key=>$value) 
$values[]="$key=".urlencode($value); 
$data_string=implode("&",$values); 
// Find out which port is needed - if not given use standard (=80) 
if(!isset($URL_Info["port"])) 
$URL_Info["port"]=80; 
// building POST-request: 
$request.="POST ".$URL_Info["path"]." HTTP/1.1n"; 
$request.="Host: ".$URL_Info["host"]."n"; 
$request.="Referer: $referern"; 
$request.="Content-type: application/x-www-form-urlencodedn"; 
$request.="Content-length: ".strlen($data_string)."n"; 
$request.="Connection: closen"; 
$request.="Cookie: $cookien"; 
$request.="n"; 
$request.=$data_string."n"; 
$fp = fsockopen($URL_Info["host"],$URL_Info["port"]); 
fputs($fp, $request); 
while(!feof($fp)) { 
$result .= fgets($fp, 1024); 
} 
fclose($fp); 
return $result; 
} 
printhr(); 
?> 

Example code 6: use the curl library. Before using the curl library, you may want to check php.ini to see if the curl extension is turned on

 
<? 
$ch = curl_init(); 
$timeout = 5; 
curl_setopt ($ch, CURLOPT_URL, 'http://www.baidu.com/'); 
curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1); 
curl_setopt ($ch, CURLOPT_CONNECTTIMEOUT, $timeout); 
$file_contents = curl_exec($ch); 
curl_close($ch); 
echo $file_contents; 
?> 

About the curl library:
Curl's official website is http://curl.haxx.se/
Curl is a FILE transfer tool that USES URL syntax and supports FTP, FTPS, HTTP HTPPS SCP SFTP, TFTP TELNET DICT FILE, and LDAP. Curl supports SSL certificates, HTTP POST, HTTP PUT, FTP upload, kerberos, upload based on HTT format, proxies, cookies, user + password proof, file transfer recovery, HTTP proxy channels, and a host of other useful tricks

 
<? 
function printarr(array $arr) 
{ 
echo "<br> Row field count: ".count($arr)."<br>"; 
foreach($arr as $key=>$value) 
{ 
echo "$key=$value <br>"; 
} 
} 
?> 

7.
Some hosts have PHP's allow_url_fopen option turned off, so you can't use file_get_contents directly to get the contents of a remote web page. You can use another function, curl.
Here's how to write file_get_contents and curl differently for the same function
Example of using the file_get_contents function:

 
< ?php 
$file_contents = file_get_contents('http://www.ccvita.com/'); 
echo $file_contents; 
?> 

Instead, use the curl function as an example:

 
< ?php 
$ch = curl_init(); 
$timeout = 5; 
curl_setopt ($ch, CURLOPT_URL, 'http://www.ccvita.com'); 
curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1); 
curl_setopt ($ch, CURLOPT_CONNECTTIMEOUT, $timeout); 
$file_contents = curl_exec($ch); 
curl_close($ch); 
echo $file_contents; 
?> 

Using the function_exists function to determine whether PHP supports a function makes it easy to write the following function

 
< ?php 
function vita_get_url_content($url) { 
if(function_exists('file_get_contents')) { 
$file_contents = file_get_contents($url); 
} else { 
$ch = curl_init(); 
$timeout = 5; 
curl_setopt ($ch, CURLOPT_URL, $url); 
curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1); 
curl_setopt ($ch, CURLOPT_CONNECTTIMEOUT, $timeout); 
$file_contents = curl_exec($ch); 
curl_close($ch); 
} 
return $file_contents; 
} 
?> 

The above function is a bit of a moot point. If your host turns off file_get_contents and curl, the above function will fail.