Discussion on: Daily Challenge #236 - RGB to Hex Conversion

[peter279k]

Here is the simple PHP solution:

function rgb($r,$g,$b) {
  $colorHexLists = [
      0 => '0',
      1 => '1',
      2 => '2',
      3 => '3',
      4 => '4',
      5 => '5',
      6 => '6',
      7 => '7',
      8 => '8',
      9 => '9',
      10 => 'A',
      11 => 'B',
      12 => 'C',
      13 => 'D',
      14 => 'E',
      15 => 'F',
  ];

  if ($r > 255) {
    $r = 255;
  }
  if ($r < 0) {
    $r = 0;
  }
  if ($g > 255) {
    $g = 255;
  }
  if ($g < 0) {
    $g = 0;
  }
  if ($b > 255) {
    $b = 255;
  }
  if ($b < 0) {
    $b = 0;
  }

  $rStringArray = [];
  if ($r <= 15) {
    $rStringArray[] = '0' . $colorHexLists[(int)($r)];
  } else {
      while(count($rStringArray) !== 2) {
          if ($r < 16) {
            $rStringArray[] = $colorHexLists[(int)($r)];
          } else {
            $rStringArray[] = $colorHexLists[(int)($r / 16)];
          }
          $r = $r % 16;
      }
  }  

  $gStringArray = [];
  if ($g <= 15) {
    $gStringArray[] = '0' . $colorHexLists[(int)($g)];
  } else {
      while(count($gStringArray) !== 2) {
          if ($g < 16) {
            $gStringArray[] = $colorHexLists[(int)($g)];
          } else {
            $gStringArray[] = $colorHexLists[(int)($g / 16)];
          }
          $g = $g % 16;
      }
  }

  $bStringArray = [];
  if ($b <= 15) {
      $bStringArray[] = '0' . $colorHexLists[(int)($b)];
  } else {
      while(count($bStringArray) !== 2) {
          if ($b < 16) {
            $bStringArray[] = $colorHexLists[(int)($b)];
          } else {
            $bStringArray[] = $colorHexLists[(int)($b / 16)];
          }
          $b = $b % 16;
      }
  }

  return implode($rStringArray) . implode($gStringArray) . implode($bStringArray);
}