键盘事件-键代码编号

最新推荐文章于 2024-12-13 12:26:29 发布

转载最新推荐文章于 2024-12-13 12:26:29 发布 · 102 阅读

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CC 4.0 BY-SA版权

原文链接：http://www.cnblogs.com/xinlinux/p/3915388.html

文章标签：

#javascript #ViewUI

本文提供了一个键盘事件处理的实验示例，通过JavaScript实现对键盘按键的全面监控，包括按键按下(onKeyDown)、按键释放(onKeyUp)及字符输入(onKeyPress)等事件，并显示按键码和修饰键状态。

<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>键盘事件全面控制</title>
<style type="text/css">
td {text-align:center}
</style>
<script language="javascript">
function init() {
    document.onkeydown = showKeyDown
    document.onkeyup = showKeyUp
    document.onkeypress = showKeyPress
}
function showKeyDown(evt) {
    evt = (evt) ? evt : window.event
    document.getElementById("pressKeyCode").innerHTML = 0
    document.getElementById("upKeyCode").innerHTML = 0
    document.getElementById("pressCharCode").innerHTML = 0
    document.getElementById("upCharCode").innerHTML = 0
    restoreModifiers("")
    restoreModifiers("Down")
    restoreModifiers("Up")
    document.getElementById("downKeyCode").innerHTML = evt.keyCode
    if (evt.charCode) {
        document.getElementById("downCharCode").innerHTML = evt.charCode
    }
    showModifiers("Down", evt)
}
function showKeyUp(evt) {
    evt = (evt) ? evt : window.event
    document.getElementById("upKeyCode").innerHTML = evt.keyCode
    if (evt.charCode) {
        document.getElementById("upCharCode").innerHTML = evt.charCode
    }
    showModifiers("Up", evt)
    return false
}
function showKeyPress(evt) {
    evt = (evt) ? evt : window.event
    document.getElementById("pressKeyCode").innerHTML = evt.keyCode
    if (evt.charCode) {
        document.getElementById("pressCharCode").innerHTML = evt.charCode
    }
    showModifiers("", evt)
    return false
}
function showModifiers(ext, evt) {
    restoreModifiers(ext)
    if (evt.shiftKey) {
        document.getElementById("shift" + ext).style.backgroundColor = "#ff0000"
    }
    if (evt.ctrlKey) {
        document.getElementById("ctrl" + ext).style.backgroundColor = "#00ff00"
    }
    if (evt.altKey) {
        document.getElementById("alt" + ext).style.backgroundColor = "#0000ff"
    }
}
function restoreModifiers(ext) {
    document.getElementById("shift" + ext).style.backgroundColor = "#ffffff"
    document.getElementById("ctrl" + ext).style.backgroundColor = "#ffffff"
    document.getElementById("alt" + ext).style.backgroundColor = "#ffffff"
}
</script>
</head>
<body onLoad="init()">
    <h1>Keyboard Event Handler Lab</h1>
    <hr>
    <form>
    <table border=2 cellpadding=2>
    <tr><th></th><th>onKeyDown</th><th>onKeyPress</th><th>onKeyUp</th></tr>
    <tr><th>Key Codes</th>
    <td ID="downKeyCode">0</td>
    <td ID="pressKeyCode">0</td>
    <td ID="upKeyCode">0</td>
    </tr>
    <tr><th>Char Codes (IE5/Mac; NN6)</th>
    <td ID="downCharCode">0</td>
    <td ID="pressCharCode">0</td>
    <td ID="upCharCode">0</td>
    </tr>
    <tr><th rowspan=3>Modifier Keys</th>
    <td><span ID="shiftDown">Shift</span></td>
    <td><span ID="shift">Shift</span></td>
    <td><span ID="shiftUp">Shift</span></td>
    </tr>
    <tr>
    <td><span ID="ctrlDown">Ctrl</span></td>
    <td><span ID="ctrl">Ctrl</span></td>
    <td><span ID="ctrlUp">Ctrl</span></td>
    </tr>
    <tr>
    <td><span ID="altDown">Alt</span></td>
    <td><span ID="alt">Alt</span></td>
    <td><span ID="altUp">Alt</span></td>
    </tr>
    </table>
    </form>
    </body>
</html>

转载于:https://www.cnblogs.com/xinlinux/p/3915388.html