Element: getElementsByTagName() method
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The
Element.getElementsByTagName() method trả về a live
HTMLCollection of elements with the given tag name.
All descendants of the
specified element are searched, but not the element itself. The returned list is
live, which means it updates itself with the DOM tree automatically.
Therefore, there is no need to call Element.getElementsByTagName() with
the same element and arguments repeatedly if the DOM changes in between calls.
When called on an HTML element in an HTML document, getElementsByTagName
lower-cases the argument before searching for it. This is undesirable when trying to
match camel-cased SVG elements (such as
<linearGradient>)
in an HTML document. Instead, use Element.getElementsByTagNameNS(),
which preserves the capitalization of the tag name.
Element.getElementsByTagName is similar to
Document.getElementsByTagName(), except that it only searches for
elements that are descendants of the specified element.
Cú pháp
getElementsByTagName(tagName)
Tham số
tagName-
The qualified name to look for. The special string
"*"đại diện cho all elements. For compatibility with XHTML, lower-case should be used.
Giá trị trả về
A live HTMLCollection of elements with a matching tag name, in the order they appear. If no elements are found, the HTMLCollection is empty.
Ví dụ
// Check the status of each data cell in a table
const table = document.getElementById("forecast-table");
const cells = table.getElementsByTagName("td");
for (const cell of cells) {
const status = cell.getAttribute("data-status");
if (status === "open") {
// Grab the data
}
}
Đặc tả kỹ thuật
| Specification |
|---|
| DOM # dom-element-getelementsbytagname |