JS keycode 事件响应

浏览数：45 / 时间：2015年06月09日

<script language="javascript">
function keyevent(){
if(event.keyCode==13)
alert("你按了回车键");
}
document.onkeydown = keyevent;//注册document.onkeydown事件
</script>

当用户按回车键时，就会执行keyevent()这个函数。可以做回车提交表单，或其它的事件！

keyCode是返回keydown何keyup事件发生的时候按键的代码，以及keypress 事件的Unicode字符；如果要使用组合键，则可以利用event.ctrlKey，event.shiftKey，event .altKey判断是否按下了ctrl键、shift键以及alt键.

常用keycode
key	code	key	code
left	37	up	38
right	39	down	40
1	49	2	50
3	51	a	65
shift	16	ctrl	17
alt	18	enter	13

示例：

<!DOCTYPE html>
<html>
<head>
    <title>键盘事件keycode</title>
</head>
<body>
    left&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;up&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;right&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;down<br />
    ctrl + up&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctrl + down<br />
    ctrl + 1&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctrl + 2&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctrl + 3<br />
    a&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctrl + a&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;ctrl + shift + a<br />
    <script type="text/javascript">
        document.onkeydown = function (event) {
            event = event || window.event;
            bCtrlKey = event.ctrlKey;
            bShiftKey = event.shiftKey;
            switch (event.keyCode) {
                case 37:
                    alert("left");
                    break;
                case 38:
                    if (bCtrlKey) {
                        alert("ctrl+up");
                        break;
                    }
                    alert("up");
                    break;
                case 39:
                    alert("right");
                    break;
                case 40:
                    if (bCtrlKey) {
                        alert("ctrl+down");
                        break;
                    }
                    alert("down");
                    break;
                case 49:
                    bCtrlKey && (alert("ctrl+1"));
                    break;
                case 50:
                    bCtrlKey && (alert("ctrl+2"));
                    break;
                case 51:
                    bCtrlKey && (alert("ctrl+3"));
                    break;
                case 65:
                    if (bCtrlKey) {
                        if (bShiftKey) {
                            alert("自定义");
                            break;
                        }
                        alert("全选");
                        break;
                    }
                    alert("a");
                    break;
                case 67:
                    bCtrlKey && (alert("复制"));
                    break;
                case 86:
                    bCtrlKey && (alert("粘贴"));
                    break;
            }
            return false;
        }
    </script>
</body>
</html>

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<script language="javascript">
     function keyevent(){
     if(event.keyCode==13)
     alert("#$%#%#^^%");
     }
     document.onkeydown = keyevent;
</script>
event.keyCode值为37﹐38﹐39﹐40对应按下的方向键分別是 左﹐上﹐右﹐下
"javascript:if (event.keyCode < 45 || event.keyCode > 57) event.returnValue = false;");
if(event.keycode==13)就代表按下的是回车键盘
"javascript:if (event.keyCode > 45 && event.keyCode < 57) event.returnValue = false;");

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