Info

This is comparing the runtimes of [ ], substr, substring, and slice in a string for large (66000 character) string size.

Preparation code

<script type="text/javascript">
  var longString = "";
  // Large = 66,000
  for (var i = 0; i < 66000; i++) {
    longString += i % 10;
  }
  var len = 4;
</script>

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for (i = 0; i < longString.length; i++) {
  longString.substring(i, i + len);
}

for (i = 0; i < longString.length; i++) {
  longString.slice(i, i + len);
}

for (i = 0; i < longString.length; i++) {
  longString.substr(i, len);
}

for (i = 0; i < longString.length; i++) {
  resultArray = new Array(len);
  for (j = 0; j < len; j++) {
    resultArray[j] = longString[i + j];
  }
  resultArray.join('');
}

for (i = 0; i < longString.length; i++) {
  resultArray = new Array(len);
  for (j = 0; j < len; j++) {
    resultArray[j] = longString.charAt(i + j);
  }
  resultArray.join('');
}

for (i = 0; i < longString.length; i++) {
  result = '';
  for (j = 0; j < len; j++) {
    result += longString[i + j];
  }
}

for (i = 0; i < longString.length; i++) {
  result = '';
  for (j = 0; j < len; j++) {
    result += longString.charAt(i + j);
  }
}

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Revisions

You can edit these tests or add even more tests to this page by appending /edit to the URL. Here’s a list of current revisions for this page:

• Revision 1: published by Kon P on 26th January 2012 and last updated 2 weeks ago
• Revision 2: published on 26th January 2012
• Revision 3: published on 18th February 2012
• Revision 4: published on 27th March 2012
• Revision 5: published on 27th March 2012
• Revision 6: published by klaus lynggard hougesen on 2nd May 2012
• Revision 7: published by Aaron Patterson on 14th May 2012
• Revision 8: published on 31st July 2012
• Revision 11: published on 29th November 2012
• Revision 12: published on 15th January 2013
• Revision 13: published on 13th February 2013
• Revision 14: published 3 days ago

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