How to get a word in string with relevant keyword?

Question

My language is Vietnamese, so I am having a problem with getting the exact word from the relevant keyword. I have one string and one keyword:

$mystring = "từ khóa a,từ khóa b, từ khóa c";
$mykeyword = "tu khoa b";

How can I use $mykeyword to get từ khóa b from $mystring?

Thank you!

Answer 1

What you want to do is called UTF-8 Normalization, I believe.

This post explains some of the foundations. Try this:

php > $mystring = "từ khóa a,từ khóa b, từ khóa c";
php > $mykeyword = "tu khoa b";
php > var_dump(transliterator_transliterate('Any-Latin; Latin-ASCII; [\u0080-\u7fff] remove', $mystring));
string(30) "tu khoa a,tu khoa b, tu khoa c"
php >

Now, you can use the normal string manipulation functions to see if $mykeyword is contained within $mystring. Note that characters which don't have ASCII translations will be removed.

Note that for this to work, you need the PHP intl module installed (often a package called php5-intl). See here.

You can also use the Normalizer and preg_replace() to strip accents:

php > var_dump(preg_replace('/\p{Mn}/u', '', Normalizer::normalize($mystring, Normalizer::FORM_KD)));
string(30) "tu khoa a,tu khoa b, tu khoa c"
php >

Yet another way is to use iconv():

php > var_dump(preg_replace('/[^a-zA-Z0-9 -]+/', '', iconv('UTF-8', 'ASCII//TRANSLIT//IGNORE', $mystring)));
string(25) "t khoa at khoa b t khoa c"

However, as you can see, the ừ didn't properly translate.