<form id="myForm">
    用户名：<input type="text" name="username"/>
    <br/>
    年龄：<input type="text" name="age"/>
    <br/>
    爱好：
    <input type="checkbox" name="hobby" value="篮球"/> 篮球
    <input type="checkbox" name="hobby" value="乒乓球"> 乒乓球
    <input type="checkbox" name="hobby" value="足球"> 足球
</form>
<input type="button" id="formBtn" value="发送">

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