Javascript detect control key held on mouseup

javascript, jquery, jquery-events

Solution

You can use the event.ctrlKey property.

$(function(){
  $('#elementId').mouseup(function(e){
    var isCtrlPressed = e.ctrlKey;
    // true or false whether ctrl is pressed or not 
  });
});

Check a running example here.

Problem

I've searched a good deal, and can't seem to find a satisfactory solution. I hope someone can help. While I am using jQuery, I am also writing many thousands of lines of JavaScript. So a "pure" JavaScript solution is just fine. I'm trying to determine if the control key is physically held down on a `mouseup` event. That's it; there are no other preconditions. Does anyone know how to do this reliably, cross-browser? I've tried storing this in a state variable by noting when the key is pressed and released: ``` // BEGIN store control key status in hash_state $().bind('keydown','ctrl',function( arg_obj_e ){ hash_state.sw_ctrldn = true; console.debug( hash_state.sw_ctrldn ); }); $().bind('keyup','ctrl',function( arg_obj_e ){ hash_state.sw_ctrldn = false; console.debug( hash_state.sw_ctrldn ); }); // END store control key status in hash_state ``` However, this really doesn't work. If you test this using Firebug and watch the console, you will see that auto-repeat seems to happen, and the value toggles. I inspected the `mouseup` event to see if there is anything useful there, but to no avail: ``` var debugEvent = function( arg_obj_e ){ var str = ''; for ( var attr in arg_obj_e ){ str += attr + ': ' + arg_obj_e[attr] + '\n'; } console.debug(str); } ``` Any help would be appreciated.

Original source