php中动态调用说明

<?php
 require_once showErrMsg.php;
 $_action = (isset($_REQUEST[action])?$_REQUEST[action]:"");
 if($_action!=null&&$_action!=){
  if(function_exists($_action)){
   eval("$_action();");
  }else{
   die(showErrMsg ( "<br>当前php文件中不存在方法[<b>".$_action."()</b>]。"));
  }
 }
?>

<?php
function showErrMsg($strMsg){
  return "<font color=red>".$strMsg."</font>";
 }
?>

<?php
class A
{
      function foo()
      {
          if (isset($this)) {
              echo '$this is defined (';
              echo get_class($this);
              echo ")n";
          } else {
              echo "$this is not defined.n";
          }
      }
}

class B
{
      function bar()
      {
        A::foo();
         //parent::foo();
      }
}

$a = new A();
$a->foo();//动态调用，因为new了对象
A::foo();//静态调用，直接用类名去调用，没有new对象
$b = new B();
$b->bar();//在对象$b中，A::foo();进行静态调用
B::bar();
?>

<?php
$url = "http://www.111cn.net/img/logo.jpg";
$filename = 'curl.gif';

getImg($url, $filename);
/*
*@通过curl方式获取制定的图片到本地
*@ 完整的图片地址
*@ 要存储的文件名
*/
function getImg($url = "", $filename = "") {
if(is_dir(basename($filename))) {
echo "The Dir was not exits";
Return false;
}
//去除URL连接上面可能的引号
$url = preg_replace( '/(?:^['"]+|['"/]+$)/', '', $url );
$hander = curl_init();
$fp = fopen($filename,'wb');
curl_setopt($hander,CURLOPT_URL,$url);
curl_setopt($hander,CURLOPT_FILE,$fp);
curl_setopt($hander,CURLOPT_HEADER,0);
curl_setopt($hander,CURLOPT_FOLLOWLOCATION,1);
//curl_setopt($hander,CURLOPT_RETURNTRANSFER,false);//以数据流的方式返回数据,当为false是直接显示出来
curl_setopt($hander,CURLOPT_TIMEOUT,60);
/*$options = array(
CURLOPT_URL=> 'http://www.111cn.net/img/logo.jpg',
CURLOPT_FILE => $fp,
CURLOPT_HEADER => 0,
CURLOPT_FOLLOWLOCATION => 1,
CURLOPT_TIMEOUT => 60
);
curl_setopt_array($hander, $options);
*/
curl_exec($hander);
curl_close($hander);
fclose($fp);
Return true;
}
?>

POST /目的程序 HTTP/1.1
Accept: */*
Referer: http://www.111cn.net
Accept-Language: zh-cn,en-us;q=0.5
Content-Type: application/x-www-form-urlencoded
User-Agent: Mozilla/4.0 (compatible; MSIE 5.0; Windows NT; .NET CLR 1.0.3705; .NET CLR 1.1.4322)
Host: 要发送到的主机地址
Content-Length: 发送数据的长度
Pragma: no-cache
Cache-Control: no-cache
username=php&password=iask   //post发送的数据

$port = $url['port'] ? $url['port'] : 80;
$fp = fsockopen($url['host'], $port, $errno, $errstr,10);
if (!$fp) return "在主机： $url[host] $port 打开socket失败，失败原因是: $errno - $errstr";
fputs($fp, sprintf("POST %s%s%s HTTP/1.0rn", $url['path'], $url['query'] ? "?" : "", $url['query']));
fputs($fp, "Host:".$url['host']."rn");
fputs($fp, "Content-type: application/x-www-form-urlencodedrn");
fputs($fp, "Content-length: " . strlen($encoded) . "rn");
fputs($fp, "Connection: closernrn");
fputs($fp, "$encoded\n");