这是我为用户输入数据表单编写的代码。
<?php
// Start the session
session_start();
?>
<!DOCTYPE html>
<html lang="en">
<head>
<title>Page Title Goes Here</title>
<meta charset="utf-8">
<link rel="stylesheet" type="text/css" href="form1.css"/>
</head>
<body>
<?php
//define variable and set to empty value
$forenameErr = "";
$forename = "";
if($_SERVER["REQUEST_METHOD"] =="POST"){
$valid = true;
if(empty($_POST["forename"])){
$forenameErr = "Forename is required";
$valid = false; //false
} else {
$forename = test_input($_POST["forename"]);
// check if name only contains letters and whitespace
if (!preg_match("/^[a-zA-Z ]*$/",$forename)) {
$forenameErr = "Only letters and white space allowed";
}
}
//if valid then redirect
if($valid){
$_SESSION['forename'] = $forename;
header('Location: testing2.php');
exit();
}
}
//check
function test_input($data) {
$data = trim($data);
$data = stripslashes($data);
$data = htmlspecialchars($data);
return $data;
}
?>
<div id="wrapper">
<h1>Welcome to Chollerton Tearoom! </h1>
<form id = "userdetail" action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]);?>" method="POST">
<fieldset id="aboutyou">
<legend id="legendauto">user information</legend>
<p>
<label for="forename">Forename: </label>
<input type="text" name="forename" id="forename" value="<?php echo $forename;?>">
<span class="error">* <?php echo $forenameErr;?></span>
</p>
<p>
<input type="submit" name="submit" value="submit" />
</p>
</fieldset>
</form>
</div>
</body>
</html>
这是另一个页面中的数据接收器php代码
<?php
session_start();
$forename = $_SESSION['forename'];
echo "<h1>Successfull submission :</h1>";
echo "<p>Forename : $forename; <p/>";
?>
我想做的是，如果用户没有输入任何值并按下提交。。。它将自动在数据中填写NULL。。。那我能做吗？？例如名字：詹姆斯。。姓氏：Null（如果用户没有在姓氏文本字段中输入任何内容）。。。
如果您希望它为NULL，如在空：中
$forename = empty($_POST["forename"]) ? NULL : $_POST["forename"];
如果您希望实际值为"NULL"，如string(4)中所示，则：
$forename = empty($_POST["forename"]) ? "NULL" : $_POST["forename"];
更新：
<?php
// Start the session
session_start();
?>
<!DOCTYPE html>
<html lang="en">
<head>
<title>Page Title Goes Here</title>
<meta charset="utf-8">
<link rel="stylesheet" type="text/css" href="form1.css"/>
</head>
<body>
<?php
// define variables and set to empty value
$firstNameError = "";
$lastNameError = "";
$error = false;
// if firstName is empty, make it NULL, else, test_input() the data.
$firstName = empty($_POST["firstName"]) ? NULL : test_input($_POST["firstName"]);
// if lastName is empty, make it NULL, else, test_input() the data.
$lastName = empty($_POST["lastName"]) ? NULL : test_input($_POST["lastName"]);
if (isset($_POST["submittingForm"])) {
/// CHECK FIRST NAME ERRORS
if ($firstName === NULL) {
// firstName is empty
$firstNameError = "First name is required!";
$error = true;
} else {
// check characters
if (!preg_match("/^[a-zA-Z ]*$/", $firstName)) {
$firstNameError = "Only letters and white spaces allowed!";
$error = true;
}
}
/// CHECK LAST NAME ERRORS
if (!preg_match("/^[a-zA-Z ]*$/", $lastName)) {
// check characters
$lastNameError = "Only letters and white spaces allowed!";
$error = true;
}
// if no error then redirect
if (!$error) {
$_SESSION['fistName'] = $firstName;
$_SESSION['lastName'] = $lastName;
header('Location: testing2.php');
exit();
}
} else {
// user did not submit form!
}
// clean input
function test_input($data) {
$data = trim($data);
$data = stripslashes($data);
$data = htmlspecialchars($data);
return $data;
}
?>
<div id="wrapper">
<h1>Welcome to Chollerton Tearoom! </h1>
<form id="userdetail" method="POST">
<fieldset id="aboutyou">
<legend id="legendauto">user information</legend>
<p>
<label for="firstName">First Name: </label>
<input type="text" name="firstName" id="firstName" value="<?php echo $firstName; ?>">
<span class="error">* <?php echo $firstNameErr;?></span>
<label for="lastName">Last Name: </label>
<input type="text" name="lastName" id="lastName" value="<?php echo $lastName; ?>">
<span class="error">* <?php echo $lastNameErr;?></span>
</p>
<p>
<input type="submit" name="submittingForm" value="submit">
</p>
</fieldset>
</form>
</div>
</body>
</html>
if ($forename == ""){
$forename = "NULL";
}
PHP代码片段
function test_input($data) {
$data = trim($data);
$data = stripslashes($data);
$data = htmlspecialchars($data);
if ($data == '') {
$data = 'NULL';
}
return $data;
}