jQuery: how to do something only if element exist? -

i'm new jquery , think question answered many times. can't suggest how find it. while writing jquery code, write constructions selector repeated:

if( $( ".someclass .someclass #someid" ).filter( ":visible" ) ) {   $( ".someclass .someclass #someid" ).filter( ":visible" ).click();   // must executed if element found.   return; } // must executed if first element not found if( $( ".someotherclass #someotherid" ).filter( ":hidden" ) ) {   $( ".someotherclass #someotherid" ).filter( ":hidden" ).show();   return; } 

as can see, selector text repeated. way re-use result of last matched selector inside "if()"? example, like:

if( $( ".someclass .someclass #someid" ).filter( ":visible" ) ) {   $( ":last-result" ).click();   return; } if( $( ".someotherclass #someotherid" ).filter( ":hidden" ) ) {   $( ":last-result" ).show();   return; } 

simply don't test, won't make error if there no matching element :

$( ".someclass .someclass #someid:visible").click(); 

this being said, can have 1 element given id, should use

$("#someid:visible").click(); 

now, supposing want test, may use

$("#someid:visible").each(function(){      var $element = $(this);       // use $element  }); 

another basic solution cache element before test :

 var $element = $("#someid");  if ($element.is(":visible")) {      // use $element  }