js修改iframe内的id

<!-- 父页面 -->
<iframe id="myIframe" src="iframe-content.html"></iframe>
<button onclick="changeIframeElementId()">Change ID</button>

<script>
function changeIframeElementId() {
    var iframe = document.getElementById('myIframe');
    var iframeDocument = iframe.contentDocument || iframe.contentWindow.document;
    
    // 假设我们要修改的元素是一个div，其原始ID为'originalId'
    var elementToChange = iframeDocument.getElementById('originalId');
    if (elementToChange) {
        elementToChange.id = 'newId';
        console.log('ID changed successfully.');
    } else {
        console.log('Element with ID "originalId" not found in iframe.');
    }
}
</script>

iframe.onload = function() {
    var elementToChange = iframeDocument.getElementById('originalId');
    if (elementToChange) {
        elementToChange.id = 'newId';
    }
};