Date: 2013sep20 Update: 2022oct21 Library: jQuery Language: javaScript Q. jQuery: Check if something exists A. Use the .length property like this:

if ($('#mything').length == 0) { // Does not exist } else { // Is there }

In fact you don't even need the compare, this is valid:

if ($('#mything').length) { // Is there }

Do NOT write length() We were just checking for one id but it works for any selector. For example to see if the document has any images:

if ($('img').length == 0) { alert('No images'); }