How can I check string contains only a-z

Question

I have a few strings like these:

$str = 'this is a test 1';
$str = 'this is a test س';
$str = 'this is a test!';
$str = 'this is a test';

And I want this output:

false // there is this number: `1`
false // there is a Arabic character: س
false // there is a exclamation mark
true // that's pure English

As you see, I need to determine a string is pure-English or not. How can I do that?

@Dagon it is just containing `a-z` characters plus whitespace. — Shafizadeh, Dec 26 '15 at 22:33
Do you mean to validate that the string has only base ASCII _letters_ and whitespace? — Michael Berkowski, Dec 26 '15 at 22:33
@Dagon That question you flagged isn't the same with mine...! It isn't sensitive to whitespace and it language is asp and mine is php. — Shafizadeh, Dec 26 '15 at 22:40

score 2 · Accepted Answer · answered Dec 26 '15 at 22:33

2

Assuming "pure English" = English letters + space:

^[a-zA-Z ]*$

[a-zA-Z ] - defines a character set containing lower and upper case letters + space
* - repeat any number of times
^$ - make sure the string is matched from the start (^) til the end ($)

answered Dec 26 '15 at 22:33

ndnenkov

Just for my information, How can I add all symbols *(`!`, `.`, `@`, `#`, `^`, `%` and etc ..)* to it? – Shafizadeh Dec 26 '15 at 22:48
@Shafizadeh, you can add them between the brackets. However, be careful - some characters have special meanings. For example don't put the `^` at the beginning of the brackets, because then it would have the meaning of negation. – ndnenkov Dec 26 '15 at 22:51

1 Answers1