client.html

<a href="server.php?name=zhangsan&age=10">server</a>

<form action="server.php" method="post">
    username: <input type="text" name="name"> <br>
    age: <input type="text" name="age"> <br>

    <input type="submit" name="sub" value="提交">

<form>  

server.php

<?php
/*
echo $_GET['name']."<br>";
echo $_GET['age']."<br>";

var_dump($_GET);
echo '<br>';
var_dump($_POST);
 */
    echo $_POST['name'];
    echo $_POST['age'];
    echo $_POST['sub'];