يمكنك استخدام هذه الوظائف:
function isNumeric(val) {
return !isNaN(parseFloat(val)) && isFinite(val);
}
function findHighestZIndex(className) {
let queryObject = document.getElementsByClassName(className);
let childNodes = Object.keys(queryObject).map(key => queryObject[key]);
let highest = 0;
var highestElem;
childNodes.forEach((node) => {
// Get the calculated CSS z-index value.
let cssStyles = document.defaultView.getComputedStyle(node);
let cssZIndex = cssStyles.getPropertyValue('z-index');
// Get any inline z-index value.
let inlineZIndex = node.style.zIndex;
// Coerce the values as integers for comparison.
cssZIndex = isNumeric(cssZIndex) ? parseInt(cssZIndex, 10) : 0;
inlineZIndex = isNumeric(inlineZIndex) ? parseInt(inlineZIndex, 10) : 0;
// Take the highest z-index for this element, whether inline or from CSS.
let currentZIndex = cssZIndex > inlineZIndex ? cssZIndex : inlineZIndex;
if ((currentZIndex > highest)) {
highest = currentZIndex;
highestElem = node;
}
});
var obj = {highestZIndex: highest, elem: highestElem};
return obj;
}
<!DOCTYPE html>
<html>
<head>
</head>
<body>
<html>
<body>
<div class="test" style="z-index: 100;" id="x">1</div>
<div class="test" style="z-index: 10;">2</div>
<div class='test' id="test">3</div>
<script>
function isNumeric(val) {
return !isNaN(parseFloat(val)) && isFinite(val);
}
function findHighestZIndex(className) {
let queryObject = document.getElementsByClassName(className);
let childNodes = Object.keys(queryObject).map(key => queryObject[key]);
let highest = 0;
var highestElem;
childNodes.forEach((node) => {
// Get the calculated CSS z-index value.
let cssStyles = document.defaultView.getComputedStyle(node);
let cssZIndex = cssStyles.getPropertyValue('z-index');
// Get any inline z-index value.
let inlineZIndex = node.style.zIndex;
// Coerce the values as integers for comparison.
cssZIndex = isNumeric(cssZIndex) ? parseInt(cssZIndex, 10) : 0;
inlineZIndex = isNumeric(inlineZIndex) ? parseInt(inlineZIndex, 10) : 0;
// Take the highest z-index for this element, whether inline or from CSS.
let currentZIndex = cssZIndex > inlineZIndex ? cssZIndex : inlineZIndex;
if ((currentZIndex > highest)) {
highest = currentZIndex;
highestElem = node;
}
});
var obj = {highestZIndex: highest, elem: highestElem};
return obj;
}
console.log(findHighestZIndex('test').elem.id);
</script>
</body>
</html>
</body>
</html>