使用表单的条件php


conditional php using a form

我正在尝试创建一个页面,用户填写该页面,然后存储表单的值,在同一页面上,只显示文本"Hi firstname lastname"及其在屏幕上显示的表单上输入的姓名。当我尝试执行此操作时,服务器出现错误(500)。

<html>
<title>PHP Example</title>
<script>
    function validation() {
        var x = document.forms["submit"]["firstname"].value;
        var y = document.forms["submit"]["lastname"].value;
        if (x == null || x == "" || y == null || y == "") {
            alert("Error");
            return false;
        } else {
            return true;
        }
    }
</script>
</html>
<?php
     if (isset($_REQUEST["firstname"]) == false) { ?>
    <form name="submit" action="test5.php" method="get" onsubmit="return validation()">
        <p>First name:
            <input type="text" name="firstname" value="Jane" />
        </p>
        <p>Last name:
            <input type="text" name="lastname" value="Doe" />
        </p>
        <input type="submit" value="Submit" />
    </form>
    <?php 
    } 
    else if (isset($_REQUEST["firstname"] == true) { 
      echo $_POST['firstname'] . $_POST['lastname'];
      echo "Hi " . $_REQUEST['firstname'] . " " . $_REQUEST['lastname'] . "!";
    } ?>
</html>

缺少括号,请更改

else if (isset($_REQUEST["firstname"] == true) { 

else if (isset($_REQUEST["firstname"]) == true) {