Question

我有一个包含3个字段的表单，我想验证这些字段。

让我们说用户犯了错误或没有引入电子邮件，然后所有其他字段（姓名和地址）重置为空白。

有没有办法在不重置名称和地址的情况下显示错误消息（需要电子邮件），以便用户不必再次引入所有值？

对于表单具有多个值的用户来说，这是一个很好的帮助。

非常感谢

请参阅下面的PHP代码：

<!DOCTYPE HTML>
<html>
<head>
<style>
.error {color: #FF0000;}
</style>
</head>
<body>

<?php
// define variables and set to empty values
$nameErr = $emailErr = $addressErr = "";
$name = $email = $address = "";

if ($_SERVER["REQUEST_METHOD"] == "POST") {

if (empty($_POST["address"])) {
 $AddressErr = "Address is required";
} else {
 $address = test_input($_POST["address"]);
// check if name only contains letters and whitespace
if (!preg_match("/^[a-zA-Z ]*$/",$address)) {
  $addressErr = "Only letters and white space allowed";
}
}


if (empty($_POST["name"])) {
 $nameErr = "Name is required";
} else {
 $name = test_input($_POST["name"]);
// check if name only contains letters and whitespace
if (!preg_match("/^[a-zA-Z ]*$/",$name)) {
  $nameErr = "Only letters and white space allowed";
}
}

if (empty($_POST["email"])) {
  $emailErr = "Email is required";
} else {
   $email = test_input($_POST["email"]);
 // check if e-mail address is well-formed
 if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
   $emailErr = "Invalid email format";
 }
 }


 <p><span class="error">* required field.</span></p>
 <form method="post" action="<?php echo  htmlspecialchars($_SERVER["PHP_SELF"]);?>">


<input type="text" name="name" placeholder="First Name">
<span class="error">* <?php echo $nameErr;?></span>
<br><br>

<input type="text" name="email" placeholder="Email">
<span class="error">* <?php echo $emailErr;?></span>
<br><br>


<input type="text" name="address" placeholder="Address">
<span class="error">* <?php echo $AddressErr;?></span>
<br><br>


<input type="submit" name="submit" value="SAVE">
</form>


<?php

if ($nameErr == '' && $emailErr == '' && $AddressErr == '') 
{

   $db = pg_connect('host=localhost dbname=test user=samuelraul password=naikaerikamber');

    $firstname = pg_escape_string($_POST['name']);
    $emailaddress = pg_escape_string($_POST['email']);
    $address = pg_escape_string($_POST['address']);

 $query = "INSERT INTO host(firstname, emailaddress, address) VALUES('" .     $firstname . "', ' '" . $emailaddress . "',  '" . $address . "')";

    $result = pg_query($db, $query);
    if (!$result) {
        $errormessage = pg_last_error();
        echo "Error with query: " . $errormessage;
        exit();
    }
    pg_close();

 }
?>

</body>
</html>

Answer 1

您可以将value="<?php echo $name;?>"用于名称字段，因为您已定义$name变量。您可以分别使用$email和$address变量用于电子邮件和地址字段

<form method="post" action="<?php echo  htmlspecialchars($_SERVER["PHP_SELF"]);?>">
    <input type="text" name="name" placeholder="First Name" value="<?php echo $name;?>">
    <span class="error">* <?php echo $nameErr;?></span>
    <br><br>
    <input type="text" name="email" placeholder="Email" value="<?php echo $email;?>">
    <span class="error">* <?php echo $emailErr;?></span>
    <br><br>
    <input type="text" name="address" placeholder="Address" value="<?php echo $address;?>">
    <span class="error">* <?php echo $AddressErr;?></span>
    <br><br>
    <input type="submit" name="submit" value="SAVE">
</form>

Answer 2

通过PHP的最简单方法如下：

<input type="text" name="name" placeholder="First Name" value="<?php echo ( isset( $_POST['name'] ) ? htmlspecialchars($_POST['name']) : '' ); ?>">

此代码检查POST [name]是否已发送到服务器，如果是，则只将内容设置为输入值。
对于其他输入，您必须将$ _POST [name]替换为例如$ _POST [电子邮件]。

另外，我会将输入类型设置为email，用于电子邮件地址。

PHP表单验证而不重置所有其他值

2 个答案: