PHP post request (custom header and fast)

php_post.php

/*
* Use curl for http to send  body for the form array, header for the head array
* Reference: http: //www.q3060.com/list3/list117/28490.html
*/
function sendPostRequest($url,$body,$header=null)
{
    $ch = curl_init ();
    curl_setopt ( $ch, CURLOPT_URL, $url );
    curl_setopt($ch, CURLOPT_HTTPHEADER, array("Expect: "));  //Increase the sending speed : 
    curl_setopt($ch, CURLOPT_POST,true);
    curl_setopt ( $ch, CURLOPT_HEADER, 0 );
    if($header!=null)
    {
      $headerArray=array();
      $i=0;
      foreach($header as $key=>$value)  //The header array is converted to HTTP header header format
      {
          $headerArray[$i]=$key.":".$value;
          $i++;
      }
       curl_setopt ( $ch, CURLOPT_HTTPHEADER, $headerArray ); 
    }
    curl_setopt ( $ch, CURLOPT_RETURNTRANSFER, true );
    $filde_string=http_build_query($body);
    curl_setopt ( $ch, CURLOPT_POSTFIELDS,$filde_string);
    $return = curl_exec ( $ch );
    curl_close ( $ch );
    return $return;
}