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<script type="text/javascript">
 function onmousedown(event) {
    var content = document.getElementById("ss");
    var output = event.type + ": <ul>";
    for (property in event) { //循环输出　ｅｖｅｎｔ内的属性／值
        output += "<li>" + property + ": " + event[property] + "</li>";
    }
    console.log(output);
    content.innerHTML = output + "</ul>";
}
</script>
<p onmousedown="onmousedown" >点击我</p>
<div id="ss"></div>

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