The following code will use a simple way to detect whether the name field contains letters and spaces. If the name field value is illegal, error message will be output:
$name = test_input($_POST["name"]); if (!preg_match("/^[a-zA-Z ]*$/",$name)) { $nameErr = "只允许字母及空格"; }
PS:
preg_match — perform regular expression matching.
Syntax:int preg_match ( string $pattern , string $subject [, array $matches [, int $flags ]] )
Search the subject string for the regular expression given by pattern content that matches the formula. If matches is provided, it will be populated with the results of the search. $matches[0] will contain text that matches the entire pattern, $matches[1] will contain text that matches the first captured subpattern in parentheses, and so on.The following code will check whether the e-mail address is legitimate in a simple way. If the e-mail address is illegal, an error message will be output:
$email = test_input($_POST["email"]); if (!preg_match("/([\w\-]+\@[\w\-]+\.[\w\-]+)/",$email)) { $emailErr = "非法邮件地址"; }
The following code will check whether the URL address is legal (the following regular expression runs in the URL containing dashes: "-"). If the URL address is illegal, an error message will be output:
$website = test_input($_POST["website"]); if (!preg_match("/\b(?:(?:https?|ftp):\/\/|www\.)[-a-z0-9+&@#\/%?=~_|!:,.;]*[-a-z0-9+&@#\/%=~_|]/i",$website)) { $websiteErr = "不合法的 URL"; }
The code is as follows:
Example
<?php // 定义变量并设为空值 $nameErr = $emailErr = $genderErr = $websiteErr = ""; $name = $email = $gender = $comment = $website = ""; if ($_SERVER["REQUEST_METHOD"] == "POST") { 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 syntax is valid if (!preg_match("/([\w\-]+\@[\w\-]+\.[\w\-]+)/",$email)) { $emailErr = "Invalid email format"; } } if (empty($_POST["website"])) {$website = "";} else { $website = test_input($_POST["website"]); // check if URL address syntax is valid (this regular expression also allows dashes in the URL) if (!preg_match("/\b(?:(?:https?|ftp):\/\/|www\.)[-a-z0-9+&@#\/%?=~_|!:,.;]*[-a-z0-9+&@#\/%=~_|]/i",$website)) { $websiteErr = "Invalid URL"; } } if (empty($_POST["comment"])) {$comment = "";} else {$comment = test_input($_POST["comment"]);} if (empty($_POST["gender"])) {$genderErr = "Gender is required";} else {$gender = test_input($_POST["gender"]);} } ?>
##
The above is the detailed content of PHP development form verification email and URL. For more information, please follow other related articles on the PHP Chinese website!