javascript实现判断鼠标的状态

<script>
function dclick() {
form1.text.value = "您双击了页面！";
}

function Click() {
form1.text.value += "您单击了页面";
}

function down() {
form1.text.value = "您按下了鼠标";
}

function up() {
form1.text.value = "您释放了鼠标"
}
</script>
</head>

<body ondblclick="dclick()" onmousedown="down()" onmouseup="up()" onclick="click()">
<form action="" id="form1" name="form1" method="post">
<label>
<textarea name="text" cols="50" rows="2"></textarea>
</label>
</form>
</body>