get element by id in Jquery

JavaScript
<script>
$(document).ready(function(){
    $("#myBtn").click(function(){
        var elmId = $("#test").attr("id");
        alert(elmId);
    });
});
</script>

<body>
    <div id="testDiv">Data of the Div</div>
    <br>
    <button type="button" id="myBtn">Show Div ID</button>
</body>$("#YourElementId").val();
Source

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