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HomeWeb Front-endJS TutorialSummary of jQuery Selector selector_jquery

//jQuery selector$
//$(expression,[context]) return jQuery
//Unit One
//The CSS definer of expression is to use CSS syntax to represent the element to be selected

// $("*"); // Represents all element tags on the page
// $("th, td") // Represents all

element tags
// $ ("a") // Indicates all element tags
// $("div#onlydiv"); // Indicates that the element $("#ID") with id=onlyidv in CSS selection is a full document match
// $("#rating"); // Represents the element with id=rating
// $("#orderedlist > li"); // Represents all sub-elements of id=orderedlist, but does not include the sub-elements Child elements under the element
// $("#orderedlist li:last"); // Represents the last element of li in id=orderedlist
// $("#orderedlist li:first"); // Represents the first element of li in id=orderedlist
// $("#orderedlist li:nth- child(0)"); //Represents the (N)th element n of li in id=orderedlist, n is the array subscript
// $("button:only-child"); //Indicates that it is the only element in the parent container in the css selection
// $(".stuff:empty"); //Indicates the css selection Empty elements in
// $(".buttons:enabled"); // Represents normally enabled elements in css selection
// $(".buttons:disabled"); // Represents css selection Non-enabled elements in
// $("input:checked"); // Represents selected elements in css selection
// $("button:not(.not)"); // Represents Remove elements in not() in css selection
// $("button.not"); // Indicates that the element $(".CLSS") with class=not in css selection is a full document match
// $("#orderedlist2 li"); // Indicates all child elements of id=orderedlist and includes the child elements of all child elements
// //alert($("#orderedlist ~ li").length) ;
// $("#orderedlist,.buttons,li"); //Elements matching css selector



//expression is selected based on element attributes
// alert($("button[@class]").length); // Represents elements with class attributes
// alert($("button[@class=not").length); // Represents an element with a class attribute and a value equal to not
// alert($('button[@class^=not').length); // Represents an element with a class attribute and a value starting with not that matches not
/ / alert($('button[@class$=not').length); // Indicates an element with a class attribute and a value ending in not that matches not
// alert($('button[@class*=not' ).length); // Represents elements with class attributes and values ​​that match not
//Expression XPATH filter XPATH syntax to represent page elements that need to be selected
//$("ol[@id^ ='orderedlist']").find("li:contains('First')").each(function(i) {
//// $(this).html( $(this).html( ) " BAM! " i );
// $(this).mouseover(function(){
// $(this).css("color","red");
// });
// $(this).mouseout(function(){
// $(this).css("color","#000");
// });
// });
//Find all elements with ol tag and attribute id=orderedlist, there are two ways to write them
//ol[@id='orderedlist'] to locate the parent element and directly use each iteration
//ol[@id='orderedlist']/* Use find('child- element').each() to iterate all child elements under the parent element

//Unit two
///$(html, [ownerDocument]) return jQuery
//This function allows passing in html element text, and the constructor will generate a jQuery object created by this HTML text. This object can be one that does not exist originally, or it can be
//$('

hello

that originally existed on the page').appendTo("h2"); //Generate a markup text and append it to the h2 tag of the page
//You can also take out the original page element and append it
//$("input", this). appendTo("h2"); //Note that the page elements taken out here are moved! rather than copied

///$(elements) return jQuery
//This function allows direct passing in the DOM
//$(document.forms[0].elements).appendTo("h2"); // You can refer to the DOM document
//$(callback) return jQuery



//The following are some instructions for the selector
/*
Basics:

#id: Get the object based on its id attribute.
element: All objects that match a certain HTML tag
.class: Get the object according to the class attribute of the object
*: Get all the objects
selector1, selector2, selectorN: Get multiple selectors Collection, do not remove duplicates

Level selector:
ancestor descendant: This selector is a space, which means to first find all objects of the first selector, and then find all its descendant nodes The object matching the second selector.
parent > child: This selector is the greater than sign, which means to first find all the objects of the first selector, and then find all the objects that match the second selector in its child nodes (not grand nodes).
prev next: This selector is the plus sign, which means to first find all the objects of the first selector, and then find the objects that follow the next node of the same level and also match the second selector.
prev ~ siblings: This selector is the ~ sign, which means to first find all objects with the first selector, and then find objects that match the second selector in all subsequent nodes at the same level.

Basic filter characters:
:first: Match the first object among multiple objects
:last: Match the last object among multiple objects
:not(selector): Match items with the content in the selector after not removed
:even: match the even number among all objects
:odd: match the odd number among all objects
:eq(index): match something A single element in the following table
:gt(index): Matches all elements greater than a certain subscript
:lt(index): Matches all elements less than a certain subscript
:header: Matches all header elements, For example, h1, h2, h3, h4, h5, h6
:animated: matches all animated elements

text filter:
:contains(text): matches the text element that has the internal content Objects, including indirect useful situations
:empty: matches all objects without child elements
:has(selector): matches all objects that contain at least one child selector
:parent: matches all parents Objects, the parent object contains those objects that only contain text

Visibility filter:
:hidden: matches all hidden objects, or the hidden type in the input
:visible: matches all visible objects

Attribute filter:
[attribute]: Matches all objects with a certain attribute
[attribute=value]: Matches objects with a certain attribute and value
[attribute!= value]: Match objects that have a certain attribute and are not a certain value
[attribute^=value]: Match objects that have a certain attribute and start with a certain value
[attribute$=value]: Match objects that have a certain attribute and end with a certain value
[attribute*=value]: Match objects that have a certain attribute and contain a certain value
[selector1] [selector2][selectorN]: Match objects that match multiple attribute selectors at the same time

sub-filter:
:nth- child(index/even/odd/equation): Match a certain subscript /even/odd/ in the child element For equation objects, :eq(index) can only match the characteristics of a sub-element of a single object, while this method can match the common characteristics of a certain sub-element of multiple objects
: first-child: matches the first child element
:last-child: Matches the last child element
These two matchers can also match all child elements of multiple parent objects
:only-child: If a parent element has only one child element, just match this sub-element

form filter
Name Type

:input Returns: Array
match the input element in the form

: text Returns: Array
Matches elements with input type text in the form

: password Returns: Array
Matches elements with input type password in the form

:radio Returns: Array
Match elements in the form whose input type is radio

:checkbox Returns: Array
Match elements in the form whose input type is checkbox

:submit Returns: Array
Match elements with input type submit in the form

:image Returns: Array
Match elements with image in the form

:reset Returns: Array
Match the elements in the form whose input type is reset

:button Returns: Array
Match the elements in the form whose input type is button

:file Returns: Array
Match elements whose input type is file in the form.

:hidden Returns: Array
Match elements whose input type is hidden in the form Element or hidden area



:enabled Returns: Array
matches all enabled elements

: disabled Returns: Array
matches all Non-enabled elements

:checked Returns: Array
matches all selected elements

:selected Returns: Array
matches all drop-down list selected elements

*/
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