input 绑定 keypress
var e = _event || window.event;
var kc = e.keyCode || e.which;// 按键的keyCode
var isShift = e.shiftKey || (kc == 16) || false;// shift键是否按住
var capsLockActived = false;
if ((kc >= 65 && kc <= 90 && !isShift)|| (kc >= 97 && kc <= 122 && isShift))capsLockActived = true;
