1.HTML結構

<div class="input-box">
			<div>
				<input type="radio" id="desc1" name="descID" value="1" checked>
				<label class="" for="desc1">使用文章連結</label>
			</div>
			<input id="artLink" type="text" name="art_link" placeholder="地址">
		</div>
		<div class="input-box">
			<div>
				<input type="radio" id="desc2" name="descID" value="2">
				<label class="" for="desc2">內容</label>
			</div>
			<div>
				<textarea name="" id="txt" cols="30" rows="10" disabled></textarea>
			</div>
		</div>
 

2.js

$("input:radio").click(function(){
		
		let textareaDom = $("#txt");
		let artLinkDom = $("#artLink");
		let radioVal = $(this).val();	

                switch(radioVal){
			case '1':
				textareaDom.attr("disabled",'disabled'); //增加屬性
				break;
			case '2':
				$('#txt').removeAttr("disabled"); //移除屬性
				break;
			default :
				console.log('default');
		}
});