PHP 擷取遠程檔案內容的函數代碼

如下函數： 複製代碼 代碼如下:<?
/**
擷取遠程檔案內容
@param $url 檔案http地址
*/
function fopen_url($url)
{
if (function_exists('file_get_contents')) {
$file_content = @file_get_contents($url);
} elseif (ini_get('allow_url_fopen') && ($file = @fopen($url, 'rb'))){
$i = 0;
while (!feof($file) && $i++ < 1000) {
$file_content .= strtolower(fread($file, 4096));
}
fclose($file);
} elseif (function_exists('curl_init')) {
$curl_handle = curl_init();
curl_setopt($curl_handle, CURLOPT_URL, $url);
curl_setopt($curl_handle, CURLOPT_CONNECTTIMEOUT,2);
curl_setopt($curl_handle, CURLOPT_RETURNTRANSFER,1);
curl_setopt($curl_handle, CURLOPT_FAILONERROR,1);
curl_setopt($curl_handle, CURLOPT_USERAGENT, 'Trackback Spam Check'); //引用垃圾郵件檢查
$file_content = curl_exec($curl_handle);
curl_close($curl_handle);
} else {
$file_content = '';
}
return $file_content;
}
?>

相關解釋：
1,ini_get : Returns the value of the configuration option as a string on success, or an empty string on failure(讀取 php.ini 設定檔中的值)
2,; Whether to allow the treatment of URLs (like http:// or ftp://) as files.
allow_url_fopen = On(設定檔中的內容)
3,fopen( "rb"): 在操作二進位檔案時如果沒有指定 'b' 標記，可能會碰到一些奇怪的問題，包括壞掉的圖片檔案以及關於 \r\n 字元的奇怪問題。
注意: 為移植性考慮，強烈建議在用 fopen() 開啟檔案時總是使用 'b' 標記。
注意: 再一次，為移植性考慮，強烈建議你重寫那些依賴於 't' 模式的代碼使其使用正確的行結束符並改成 'b' 模式。
4,strtolower -- Make a string lowercase
5,curl_init() :curl_init -- Initialize a cURL session(初始化一個cUrl會話)
resource curl_init ( [string url] )
Initializes a new session and return a cURL handle for use with the curl_setopt(), curl_exec(), and curl_close() functions.
url--If provided, the CURLOPT_URL option will be set to its value. You can manually set this using the curl_setopt() function.
Returns a cURL handle on success, FALSE on errors.
6,curl_setopt -- Set an option for a cURL transfer(提供設定)
bool curl_setopt ( resource ch, int option, mixed value )
Sets an option on the given cURL session handle. (具體請看 PHP 手冊) There:
CURLOPT_URL ：The URL to fetch. You can also set this when initializing a session with curl_init().
CURLOPT_CONNECTTIMEOUT ：The number of seconds to wait whilst trying to connect. Use 0 to wait indefinitely.(無限期等待 設定為 0)
CURLOPT_RETURNTRANSFER ：TRUE to return the transfer as a string of the return value of curl_exec() instead of outputting it out directly.
CURLOPT_FAILONERROR ：TRUE to fail silently if the HTTP code returned is greater than or equal to 400. The default behavior is to return the page normally, ignoring the code.
CURLOPT_USERAGENT ：The contents of the "User-Agent: " header to be used in a HTTP request.
7,curl_exec : Perform a cURL session, This function should be called after you initialize a cURL session and all the options for the session are set.
如果成功則返回 TRUE，失敗則返回 FALSE。 However, if the CURLOPT_RETURNTRANSFER option is set, it will return the result on success, FALSE on failure
8,curl_close -- Close a cURL session

下面是一些參考代碼:
PHP 採集程式 常用函數
PHP 採集擷取指定網址的內容