Curl(), file_get_contents(), and snoopy.class.php are the three tools used in remote page crawling or collection. I still prefer to use snoopy.class.php because of its efficiency. It is relatively high and does not require server-specific configuration support. It can be used in ordinary virtual hosts. file_get_contents() is slightly less efficient. In common failure situations, curl() is very efficient. It supports multi-threading, but you need to enable the curl extension. . The following are the steps to enable curl extension:
1. Copy the three files php_curl.dll, libeay32.dll, ssleay32.dll under the PHP folder to system32;
2. Remove the semicolon in extension=php_curl.dll in php.ini (c:WINDOWS directory);
3. Restart apache or IIS.