Php 旋度输出不显示

下面是我的代码，但没有显示输出。现在，我暂时将yahoo.com显示为

curl

输出，但实际输出url不同。谁能告诉我代码中有什么问题吗

<?php
    $myurl = "www.yahoo.com";
    curl_setopt ($ch, CURLOPT_URL, $myurl);
    curl_setopt ($ch, CURLOPT_HEADER, 0);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    $result= curl_exec ($ch); //execute and get the results
    echo $result; //display the reuslt
    curl_close($ch);
?>

试试这个：

//Add $ch = curl_init();
$ch = curl_init();

$myurl = "www.yahoo.com";
curl_setopt ($ch, CURLOPT_URL, $myurl);
curl_setopt ($ch, CURLOPT_HEADER, 0);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
$result= curl_exec ($ch); //execute and get the results
echo $result; //display the reuslt
curl_close($ch);

---

您没有初始化卷曲，请使用以下方法：

 <?php

 $myurl = "www.yahoo.com";
 $ch = curl_init();
 curl_setopt ($ch, CURLOPT_URL, $myurl);
 curl_setopt ($ch, CURLOPT_HEADER, 0);
 curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
 $result= curl_exec ($ch); //execute and get the results
 echo $result; //display the reuslt
 curl_close($ch);
 ?>