New to Regex

[cry of war]

Hello im kind of new to regex i know the very very basic basics like [0-9] and [a-z] but i have a few if strings that i need a regex for so i can See if the whole value or string is only numbers or only letters

 

Numbers

1235415=>true

1244p123=>false

.12235135=>false

and so on

 

Letters

aldkfjalsdf=>true

adflkjadfl1=>false

.aldkfjasldf=>false

and so on

 

if (preg_match($match,$string))
		{
		$x="2";
		}

 

any help with this problem(lack of knowledge) would be greatly appreciated

[Daniel0]

I don't understand the problem. You haven't explained a problem but rather what [0-9] and [a-z] mean.

[effigy]

Only digits: /\A\d+\z/

Only letters (ASCII): /\A[a-z]+\z/i

[jcd]

Are you looking for 1 regex which will allow both? If so this will do it I think:

 

$subject = 'asdasdadrg';

echo preg_match('%\A(\d)?(?(1)\d*|[A-Za-z]*)\z%', $subject) ? 'TRUE' : 'FALSE';

[jcd]

I've just realised the method above is a silly way of doing it (im new at this...).

 

If you do want to combine them better to do:

 

echo preg_match('%\A(\d+|[A-Za-z]+)\z%', $subject) ? 'TRUE' : 'FALSE';

[cry of war]

I was looking for a regex that tells you that the whole string is or is not only letters or is or isnt only letters

 

1235415=>true (all numbers)

1244p123=>false (not all numbers because of "p")

.12235135=>false (not all numbers because of ".")

and so on

 

Letters

aldkfjalsdf=>true(all letters)

adflkjadfl1=>false(not all letters because of "1")

.aldkfjasldf=>false(not all letters because of ".")

 

would i use preg_match_all will it check to see if the whole string only has only letters or only numbers??

[Daniel0]

^[0-9]+$ and ^[a-zA-Z]+$ can do that, but why not just use functions like ctype_alpha() to determine if it only consists of alphabetic characters (a-z uppercase and lowercase) and ctype_digit() to determine if it only consists of digits (0-9) (is_numeric() won't work as it will accept floats as well)?