I'm building a virtual keyboard in jQuery, using keycode events to tigger an append, but keycode combinations are throwing me for a loop. Here's an example:
I want to append a questionmark only when both the SHIFT key (keycode 16) and slash key (keycode 191) are pressed together. I thought the && operator would help, but this only appends the slash:
$(document).keydown(function(e) {
if (e.keyCode == 16 && e.keyCode == 188 ) {
$('#mydiv').append('<span>?</span>');
}
});
Any suggestions or idea why && isn't working, and what might work? Thanks!
Checking e.keyCode == 16 && e.keyCode == 188
won't do anything useful because e.keyCode
won't be both 16 and 188 at the same time. The &&
operator is a logical conjunction so it evaluates to true if the expressions on both sides of it are true.
I think you want to look at e.shiftKey
; if that's true then the Shift key is down, if e.shiftKey
is false then Shift is not down:
if(e.shiftKey && e.keyCode == 191) {
// ?
}
else if(!e.shiftKey && e.keyCode == 191) {
// /
}
Because each key creates its own keydown event, it will never be possible for keyCode
to equal both 16 and 188.
Luckily the SHIFT state is stored in event.shiftKey
:)
try this
$(document).keydown(function(e) {
if (e.shiftKey){
if (e.which == 188) {
alert('both');
}
}
});
来源:https://stackoverflow.com/questions/7962025/combining-keycode-events-in-jquery