php string 截取

strCut.php

  // 字符截取
  // Truncate ?
  function strCut($sourceStr, $cutLength) {
    $result = '';
    $i = 0;
    $n = 0;
    $sourceStrLen = strlen($sourceStr);

    while (($n < $cutLength) and ($i <= $sourceStrLen)) {
      $temp = substr($sourceStr, $i, 1);
      $asciiCode = ord($temp);
      
      if ($asciiCode >= 224) {
        $result = $result . substr($sourceStr, $i, 3);
        $i = $i + 3;
        $n++;

      } elseif ($asciiCode >= 192) {
        $result = $result . substr($sourceStr, $i, 2);
        $i=$i+2;
        $n++;

      } elseif ($asciiCode >= 65 && $asciiCode <= 90) {
        $result = $result . substr($sourceStr, $i, 1);
        $i = $i + 1;
        $n++;

      } else {
        $result = $result . substr($sourceStr, $i, 1);
        $i = $i + 1;
        $n = $n + 0.5;
      }
    }

    if ($sourceStrLen > $cutLength) {
      $result = $result . '...';
    }

    return $result;
  }