<form>

猫:<input type="radio" name="pet" id="cats"><br>

狗:<input type="radio" name="pet" id="dogs">

</form>

<p>单击下面的按钮禁用第一个单选框</p>

<button onclick="disableElement()">禁用单选框按钮</button>

<script>

function disableElement(){

    document.getElementById("cats").disabled=true;

}

</script>

​