1.获取from用户输入
PHP 中的 $_GET 和 $_POST 变量用于检索表单中的信息
例:
index.html
<html>
<head>
<meta charset="utf-8">
<title>from</title>
</head>
<body>
<form action="index1.php" method="post">
名字: <input type="text" name="fname">
年龄: <input type="text" name="age">
<input type="submit" value="提交">
</form>
</body>
</html>
index1.php
<?php
header("content-type:text/html;charset=GBK");
echo ("欢迎:".$_POST["fname"]);
echo("<br>");
echo ("你的年龄是:".$_POST["age"]."岁");
?>!
2.获取select选择框数据
表单使用 GET 方式获取数据,action 属性值为空表示提交到当前脚本,我们可以通过 select 的 name 属性获取下拉菜单的值:
例:
<?php
header("content-type:text/html;charset=GBK");
$q = isset($_GET['q'])? htmlspecialchars($_GET['q']) : '';
if($q) {
if($q =='BAIDU') {
echo '百度<br>http://www.baidu.com';
} else if($q =='GOOGLE') {
echo 'Google 搜索<br>http://www.google.com';
} else if($q =='TAOBAO') {
echo '淘宝<br>http://www.taobao.com';
}
} else {
?>
<form action="" method="get">
<select name="q">
<option value="">选择一个站点:</option>
<option value="BAIDU">百度</option>
<option value="GOOGLE">谷歌</option>
<option value="TAOBAO">淘宝</option>
</select>
<input type="submit" value="提交">
</form>
<?php
}
?>
htmlspecialchars() 函数把预定义的字符转换为 HTML 实体。
预定义的字符是:
- & (和号)成为 &
- " (双引号)成为 "
- ' (单引号)成为 '
- < (小于)成为 <
- > (大于)成为 >
3.获取select多选框数据
如果下拉菜单是多选的( multiple="multiple"),我们可以通过将设置 select name="q[]" 以数组的方式获取,以下使用 POST 方式提交,代码如下所示:
例:<?php
header("content-type:text/html;charset=GBK");
$q = isset($_POST['q'])? $_POST['q'] : '';
if(is_array($q)) {
$sites = array(
'BAIDU' => '菜鸟教程: http://www.baidu.com',
'GOOGLE' => 'Google 搜索: http://www.google.com',
'TAOBAO' => '淘宝: http://www.taobao.com',
);
foreach($q as $val) {
// PHP_EOL 为常量,用于换行
echo $sites[$val] . PHP_EOL;
}
} else {
?>
<form action="" method="post">
<select multiple="multiple" name="q[]">
<option value="">选择一个站点:</option>
<option value="BAIDU">百度</option>
<option value="GOOGLE">谷歌</option>
<option value="TAOBAO">淘宝</option>
</select>
<input type="submit" value="提交">
</form>
<?php
}
?>
3.获取单选框数据
PHP 单选按钮表单中 name 属性的值是一致的,value 值是不同的,代码如下所示:
<?php
header("content-type:text/html;charset=GBK");
$q = isset($_GET['q'])? $_GET['q'] : '';
if($q) {
if($q =='baidu') {
echo '百度<br>http://www.baidu.com';
} else if($q =='GOOGLE') {
echo 'Google 搜索<br>http://www.google.com';
} else if($q =='TAOBAO') {
echo '淘宝<br>http://www.taobao.com';
}
} else {
?><form action="" method="get">
<input type="radio" name="q" value="baidu" />Runoob
<input type="radio" name="q" value="GOOGLE" />Google
<input type="radio" name="q" value="TAOBAO" />Taobao
<input type="submit" value="提交">
</form>
<?php
}
?>
4.checkbox复选框
<?php
header("content-type:text/html;charset=GBK");
$q = isset($_POST['q'])? $_POST['q'] : '';
if(is_array($q)) {
$sites = array(
'BAIDU' => '百度: http://www.baidu.com',
'GOOGLE' => 'Google 搜索: http://www.google.com',
'TAOBAO' => '淘宝: http://www.taobao.com',
);
foreach($q as $val) {
// PHP_EOL 为常量,用于换行
echo $sites[$val] . PHP_EOL;
}
} else {
?><form action="" method="post">
<input type="checkbox" name="q[]" value="BAIDU"> Runoob<br>
<input type="checkbox" name="q[]" value="GOOGLE"> Google<br>
<input type="checkbox" name="q[]" value="TAOBAO"> Taobao<br>
<input type="submit" value="提交">
</form>
<?php
}
?>
5.表单验证
<!DOCTYPE HTML>
<html>
<head>
<meta charset="utf-8">
<title>fromValidate</title>
<style>
.error {color: #FF0000;}
</style>
</head>
<body>
<?php
header("content-type:text/html;charset=GBK");
// 定义变量并默认设置为空值
$nameErr = $emailErr = $genderErr = $websiteErr = "";
$name = $email = $gender = $comment = $website = "";
if ($_SERVER["REQUEST_METHOD"] == "POST")
{
if (empty($_POST["name"]))
{
$nameErr = "请输入姓名";
}
else
{
$name = test_input($_POST["name"]);
// 检测名字是否只包含字母跟空格
if (!preg_match("/^[a-zA-Z ]*$/",$name))
{
$nameErr = "只允许字母和空格";
}
}
if (empty($_POST["email"]))
{
$emailErr = "请输入邮箱";
}
else
{
$email = test_input($_POST["email"]);
// 检测邮箱是否合法
if (!preg_match("/([\w\-]+\@[\w\-]+\.[\w\-]+)/",$email))
{
$emailErr = "非法邮箱格式";
}
}
if (empty($_POST["website"]))
{
$website = "";
}
else
{
$website = test_input($_POST["website"]);
// 检测 URL 地址是否合法
if (!preg_match("/\b(?:(?:https?|ftp):\/\/|www\.)[-a-z0-9+&@#\/%?=~_|!:,.;]*[-a-z0-9+&@#\/%=~_|]/i",$website))
{
$websiteErr = "非法的 URL 的地址";
}
}
if (empty($_POST["comment"]))
{
$comment = "";
}
else
{
$comment = test_input($_POST["comment"]);
}
if (empty($_POST["gender"]))
{
$genderErr = "请输入性别";
}
else
{
$gender = test_input($_POST["gender"]);
}
}
function test_input($data)
{
$data = trim($data);
$data = stripslashes($data);
$data = htmlspecialchars($data);
return $data;
}
?>
<h2>PHP 表单验证</h2>
<form method="post" action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]);?>">
名字: <input type="text" name="name" value="<?php echo $name;?>">
<span class="error">* <?php echo $nameErr;?></span>
<br><br>
E-mail: <input type="text" name="email" value="<?php echo $email;?>">
<span class="error">* <?php echo $emailErr;?></span>
<br><br>
网址: <input type="text" name="website" value="<?php echo $website;?>">
<span class="error"><?php echo $websiteErr;?></span>
<br><br>
备注: <textarea name="comment" rows="5" cols="40"><?php echo $comment;?></textarea>
<br><br>
性别:
<input type="radio" name="gender" <?php if (isset($gender) && $gender=="female") echo "checked";?> value="girl">女
<input type="radio" name="gender" <?php if (isset($gender) && $gender=="male") echo "checked";?> value="man">男
<span class="error">* <?php echo $genderErr;?></span>
<br><br>
<input type="submit" name="submit" value="Submit">
</form>
<?php
echo "<h2>您输入的内容是:</h2>";
echo $name;
echo "<br>";
echo $email;
echo "<br>";
echo $website;
echo "<br>";
echo $comment;
echo "<br>";
echo $gender;
?>
</body>
</html>