Apply title-case to all words in string except for nominated acronyms

Example Input: SMK SUNGAI PUNAI

My Code:

$school = 'SMK SUNGAI PUNAI';
echo ucwords(strtolower($school));

Unwanted Output: Smk Sungai Punai

Question

How to make the output SMK Sungai Punai which allows SMK to remain in ALL-CAPS.

Update.

The problem I have list of 10,000 school names. 开发者_开发知识库From PDF, I convert to mysql. I copied exactly from PDF the name of schools -- all in uppercase.

How can I implement conditional title-casing?

---

As far as I understand you want to have all school names with the first character of every word in uppercase and exclude some special words ($exceptions in my sample) from this processing.

You could do that like this:

   function createSchoolName($school) {
      $exceptions = array('SMK', 'PTS', 'SBP');
      $result = "";
      $words = explode(" ", $school);
      foreach ($words as $word) {
          if (in_array($word, $exceptions))
              $result .= " ".$word;
          else
              $result .= " ".strtolower($word);
      }
      return trim(ucwords($result));
   }

echo createSchoolName('SMK SUNGAI PUNAI');

This example would return SMK Sungai Punai as required by your question.

---

You can very simply create a pipe-delimited set of excluded words/acronyms, then use (*SKIP)(*FAIL) to prevent matching those whole words.

mb_convert_case() is an excellent function to call because it instantly provides TitleCasing and it is multibyte safe.

Code: (Demo)

$pipedExclusions = 'SMK|USA|AUS';
echo preg_replace_callback(
         '~\b(?:(?:' . $pipedExclusions . ')(*SKIP)(*FAIL)|\p{Lu}+)\b~u',
         fn($m) => mb_convert_case($m[0], MB_CASE_TITLE),
         'SMK SUNGAI PUNAI'
     );
// SMK Sungai Punai

---

There's no really good way to do it. In this case you can assume it's an abbreviation because it's only three letters long and contains no vowels. You can write a set of rules that look for abbreviations in the string and then uppercase them, but in some cases it'll be impossible... consider "BOB PLAYS TOO MUCH WOW."

---

You can use something like this:

<?php
$str = 'SMK SUNGAI PUNAI';
$str = strtolower($str);
$arr = explode(" ", $str);

$new_str = strtoupper($arr[0]). ' ' .ucfirst($arr[1]). ' ' .ucfirst($arr[2]);
echo '<p>'.$new_str.'</p>';

// Result: SMK Sungai Punai
?>