<h3>访问 LABEL 元素</h3>

<label id="myLabel" for="male">Male</label>

<input type="radio" name="sex" id="male" value="male"><br>

<p>点击按钮获取 label 绑定的元素的 id</p>

<p id="demo"></p>

<button onclick="myFunction()">尝试一下</button>

<script>

function myFunction(){

    var x = document.getElementById("myLabel").htmlFor;

    document.getElementById("demo").innerHTML = x;

};

</script>

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