注：本文内容摘录自《Learning jQuery (4th Edition)》。
After creating a jQuery object using $(), we can alter the set of matched elements we are working with by calling one of these DOM traversal methods.
目录
Filtering
| Traversal method | Returns a jQuery object containing… |
|---|---|
| .filter(selector) | Selected elements that match the given selector. |
| .filter(callback) | Selected elements for which the callback function returns true. |
| .eq(index) | The selected element at the given 0-based index. |
| .first() | The first selected element. |
| .last() | The final selected element. |
| .slice(start, [end]) | Selected elements in the given range of 0-based indices. |
| .not(selector) | Selected elements that do not match the given selector. |
| .has(selector) | Selected elements that have a descendant matching selector. |
Descendants
| Traversal method | Returns a jQuery object containing… |
|---|---|
| .find(selector) | Descendant elements that match the selector. |
| .contents() | Child nodes (including text nodes). |
| .children([selector]) | Children nodes, optionally filtered by a selector. |
Siblings
| Traversal method | Returns a jQuery object containing… |
|---|---|
| .next([selector]) | The sibling immediately following each selected element, optionally filtered by a selector. |
| .nextAll([selector]) | All siblings following each selected element, optionally filtered by a selector. |
| .nextUntil([selector], [filter]) | All siblings following each selected element up to and not including the first element matching selector, optionally filtered by an additional selector. |
| .prev([selector]) | The sibling immediately preceding each selected element, optionallly filtered by a selector. |
| .prevAll([selector]) | All siblings preceding each selected element, optionally filtered by a selector. |
| .prevUntil([selector], [filter]) | All siblings preceding each selected element up to and not including the first element matching selector, optionally filtered by additional selector. |
| .siblings([selector]) | Allsiblings, optionally filtered by a selector. |
| Traversal method | Returns a jQuery object containing… |
|---|---|
| .parent([selector]) | The parent of each selected element, optionally filtered by a selector. |
| .parents([selector]) | All ancestors, optionally filtered by a selector. |
| .parentsUntil([selector], [filter]) | All ancestors of each selected element up to and not including the first element matching selector, optionally filtered by an additional selector. |
| .closest(selector) | The first element that matches the selector, starting at the selected element and moving up through its ancestors in the DOM tree. |
| .offsetParent() | The positioned parent, either relative or absolute of the first selected element. |
Collection manipulation
| Traversal method | Returns a jQuery object containing… |
|---|---|
| .add(selector) | The selected elements, plus any additional elements that match the given selector. |
| .addBack() | The selected elements, plus the previous set of selected elements on the internal jQuery stack. |
| .end() | The previous set of selected elemetns on the internal jQuery stack. |
| .map(callback) | The result of the callback function when called on each selected element. |
| .pushStack(elements) | Add a collection of DOM elements onto the jQuery stack.. |
Working with selected elements
| Traversal method | Returns a jQuery object containing… |
|---|---|
| .is(selector) | Determines whether any matched element is matched by the given selector expression. |
| .index() | Gets the index of the matched element in relation to its siblings. |
| .index(element) | Gets the index of the given DOM node within the set of matched elements. |
| $.contains(a, b) | Determines whether DOM node b contains DOM node a. |
| .each(callback) | Iterates over the matched elements, executing callback for each element. |
| .length | Gets the number of matched elements. |
| .get() | Gets an array of DOM nodes corresponding to the matched elements. |
| .get(index) | Gets the DOM node corresponding to the matched element at the given index. |
| .toArray() | Gets an array of DOM nodes corresponding to the matched elements. |