Javascript未正确检测div是否为空

var divElement = document.getElementById("myDiv");
if (divElement.innerHTML.trim() === "") {
    console.log("div is empty");
} else {
    console.log("div is not empty");
}

var divElement = document.getElementById("myDiv");
if (divElement.textContent.trim() === "") {
    console.log("div is empty");
} else {
    console.log("div is not empty");
}

var divElement = document.getElementById("myDiv");
if (divElement.childNodes.length === 0) {
    console.log("div is empty");
} else {
    console.log("div is not empty");
}