Verification email and URL

1. Match name

"/^[a-zA-Z]*$/"
Only spaces and letters are allowed, "^" means the beginning, "$" means the end, [a -zA-Z ] represents a character from a-z or A-Z or a space.

Example:

$name = test_input($_POST["name"]); if (!preg_match("/^[a-zA-Z ]*$/",$name )) { $nameErr = "Only letters and spaces allowed!"; }

2. Match E-mail

“/([\w-]+\@[\w-] +.[\w-]+)/”
“\w” matches any word character including an underscore. Equivalent to '[A-Za-z0-9_]';
+ Matches the previous subexpression one or more times;
"-" matches "-".

3. Match URL

“/\b(?:(?:https?|ftp):\/\/|www.)[-a-z0-9+&@ #\/%?=~_|!:,.;]*[-a-z0-9+&@#\/%=~_|]/i”

The red lines are all marked Regular expression.

Regular expression, also known as regular expression. (English: Regular Expression, often abbreviated as regex, regexp or RE in code), a concept in computer science. Regular tables are usually used to retrieve and replace text that matches a certain pattern (rule).

Regular expressions will be learned in the following advanced PHP tutorials. You can use them first when learning forms, just for understanding.

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