如何为任何字符和空格制作正则表达式

Question

I'm making a search form, so I want the user to enter any word or string which contains alpha numeric and space between the words.

I want to allow alpha numeric and spaces in the search bar but so far I'm not successful. I did research on google to find something that can help me to do this but so far no luck. I need your help on how to write the regular expression for preg_match So what i am trying to do here is replace any character that is not 0-9 a-z A-Z and space be replaced with ""

$searchq = mysql_prep(urldecode($_GET['q']));
$searchq = preg_replace("#[^0-9a-z\s+]#i", "", $searchq);

EDIT: After getting deep into what is happening and what i want to achieve, i found out that the problem is with my query and not my regex ! If the user enters for example first name and last name eg John Doe, i want the search result to get back with John doe from database ! so I need please your help with my query on how can i make this achievable, i have 2 columns one for First name which is "first_name" and one for last name which is "last_name"

here is my query :

$query_search2 = "SELECT * FROM users_table WHERE first_name LIKE '%$searchq%' OR last_name LIKE '%$searchq%' OR username LIKE '%$searchq%' OR first_name LIKE '%$searchq%' AND last_name LIKE '%$searchq%'";

Answer 1

You can use the following Regex, which will find All alphabets regardless of case. A-Z, a-z, 0-9, white spaces which includes tabs, and underscore.

Regex: '(?:\w+|\s+){1,}'

If you do not want to capture Underscore, you can use the following:

Regex: '([A-Za-z0-9]+|\s+){1,}'