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JavaScript AJAX Basics (retiring) Programming AJAX Parsing JSON Data

Andrew Youngwerth
Andrew Youngwerth
10,188 Points
Posted by Andrew Youngwerth
Andrew Youngwerth
10,188 Points

Is there a reason onreadystatechange doesn't follow the camelCase convention?

For example:

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function () {
      if (xhr.readyState === 4) {
          document.getElementById('ajax').innerHTML = xhr.responseText;
      }
};

notice xhr.onreadystatechange is not camelCased but xhr.responseText is. Is there a reason for this that I've missed?

1 Answer

Nicholas Hebb
Nicholas Hebb
18,872 Points

A lot of the javascript events don't follow the camel case conventions (onclick, onmouseover, ...). So I guess the rule of thumb is that your methods should be camel case, but don't always expect events to follow suit because many were created before casing conventions became uniform.

Andrew Youngwerth
Andrew Youngwerth
10,188 Points
Andrew Youngwerth
Andrew Youngwerth
10,188 Points

Thanks! It hadn't even occurred to me that those events didn't follow camelCase.