PHP form validation email and URL

PHP Forms - Validating Emails and URLs

In this chapter we will introduce how to validate names, e-mails, and URLs.

PHP - Validate Name

The following code will detect in a simple way whether the name field contains letters and spaces , if the name field value is illegal, an error message will be output:

$name = test_input($_POST["name"]); if (!preg_match("/^[a-zA-Z ]*$/",$name)) { $nameErr = "只允许字母和空格"; }

preg_match — perform regular expression matching.

Syntax:

int preg_match ( string $pattern , string $subject [, array $matches [, int $flags ]] )

in subject string Search for content that matches the regular expression given by pattern. 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.

PHP - Verification Email

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 = "非法邮箱格式"; }

PHP - Verify URL

The following code It will check whether the URL address is legal (the following regular expression operation URL contains 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 = "非法的 URL 的地址"; }

PHP - Verify Name , E-mail, and URL

The code is as follows:

The writing methods and rules of some regular expressions in the example will be discussed in the next chapter.