JavaScript-----判断Caps Lock是否开启

$scope.capsLockState = ''; // Caps Lock状态(空为未确认,on为打开CapsLock,off为CapsLock关闭)

$scope.checkCapsLock = function(event) {

    var keyCode = event.keyCode || event.which;

 

    var isShift = event.shiftKey || (keyCode == 16) || false;

    var c1 = (keyCode >= 65 && keyCode <= 90) && ! isShift; // Caps Lock 打开，且没有按住shift键

    var c2 = (keyCode >= 97 && keyCode <= 122) && isShift; // Caps Lock 打开，且按住shift键

    var c3 = (keyCode >= 65 && keyCode <= 90) && isShift; // Caps Lock 关闭，且按住shift键

    var c4 = (keyCode >= 97 && keyCode <= 122) && ! isShift; // Caps Lock 关闭，且没有按住shift键

    if (c1 || c2) {

        $scope.capsLockState = 'on';

    }

    if (c3 || c4) {

        $scope.capsLockState = 'off';

    }

};

$scope.checkCapsLockKeyUp = function(event) {

    var e = event || window.event;

    if (e.keyCode == 20 && $scope.capsLockState != '') {

        if ($scope.capsLockState == 'on') {

            $scope.capsLockState = 'off';

        } else {

            $scope.capsLockState = 'on';

        }

    }

};

<input type="password"  ng-keypress="checkCapsLock($event);" ng-keyup="checkCapsLockKeyUp($event);">

<div  ng-show="passwordHasFocus && capsLockState == 'on'">
    大写已开启
</div>