Nei tichifanira uye sei kunyora JQuery-selector?

Modern dandemutande mugadziri harifaniri chete ishe zvinokosha zviri HTML, iyo CSS uye JavaScript, asi kukwanisa kushanda muna JQuery raibhurari, iro rinonyanya nesungano pakati JavaScript pamwe HTML-magwaro. Kuti rinobvumira anokurumidza kuwana chero chinhu Dom (chikumbiro zvirongwa inowanikwa rinopa mukana kugutsikana HTML-mafaira) uye konzera navo. The chikuru STRUCTURAL zviumbu raibhurari ndivo chikwata. Kuti kushandisa rimwe kana rimwe chikwata, unofanira kuva JQuery-selector.

Formula selectors muna JQuery raibhurari

The selectors muna JQuery kwakavakirwa kushandiswa mune CSS. Ivo vanofanira kusarudza zvinhu HTML-faira, kuzvishandisa kuti izvi kana dzimwe nzira vachikorovhera pavo (chikwata). Search rinoitwa nomukombiyuta selector $ () ushande. Somuenzaniso, $ ( 'div').

The selectors inogona Classified zvichienderana sei kusarudzwa zvinhu:

• zvinhu;
• kubudikidza chizenga;
• vakuru vakuru;
• gutsikana;
• pamusoro ezvinhu;
• Kusarudza minda chimiro;
• vamwe.

Key selectors

Muna 90% nyaya paaishandisa raibhurari iri rinoshandiswa JQuery-selector kuva huru boka. Vose nyore chaizvo uye yakajeka. Ngatikurukurei chimwe nechimwe chazvo:

• * - anosarudza zvose peji okunze, kusanganisira musoro, muviri, etc.
• p / div / sidebar / ... - anosarudza zvinhu zvose zvine chokuita zvakafanorongwa Tag (kureva kuti p.div, sidebar, etc ...);
• .myClass / p.myClass - anosarudza okunze ane zita wainyatsotaura kirasi;
• # MyID / p # myID -. Anosarudza munhu chinhu chete kupiwa ID.

Heuno muenzaniso. Toti tinofanira kusarudza zvinhu zvose papeji pamwe ndima kirasi kupinda achava sezvinotevera: (. Ndima) $. Kana zvakakodzera chete S. zvezvidzidzo mukirasi iyi, nyora: $ (p.par).

vanoti selectors

Unogona kushandisa JQuery huru-selector, kana tichida kusarudza chinhu chomumwe chero kirasi ane ID kana kusarudza zvinhu zvose papeji. Zvisinei, pane zviitiko kana chinhu asina kirasi kana ID. Imhaka ichi uye kune pazviridzwa kubudikidza chizenga. Vanobvumira here kuti kusarudzwa pane zvimwe chizenga pamusoro HTML-okunze, akadai href kana src. Izvi chizenga zvakanyorwa mativi mumabhuraketi [].

The nyore muenzaniso: $ ([src]) - anosarudza zvinhu zvose zvine src chizenga. Zvinokwanisika kuderedza muenzaniso nokuda chaiyo vamwe chizenga ukoshi: $ ([src = 'http: // nzvimbo / nyaya / 132222 / ukoshi']).

Unogona kushandisa mamwe JQuery selectors kana uchida kuderedza kusango yakasarurwa. Somuenzaniso, $ (p [ruvara = yebhuruu] [size = 12]) - vanosarudzwa chete avo okunze S., vane zvitema ruvara uye kukura 12.

Selectors gutsikana

Pakadaro, kana iwe usingagoni sarudza zvinhu zvakavakirwa unhu kana zvinokosha selectors, unofanira kureva kwavo kugutsikana. In zvachose mune 4 selector iyi mhando:

• : Mariri - anosarudza zvinhu ane wainyatsotaura acho;
• : Ko - anosarudza zvinhu kuti ane zvimwe zvinhu yo rwokuyera narwo;
• : Parent - anosarudza zvinhu kuti ane umwe;
• : Empty - anosarudza zvinhu dzinenge dzisina umwe.

Heuno muenzaniso. Kuti usarudze zvinhu zvose div, ine mashoko ari Hello, unofanira kunyora $ (div: rine ( 'Hesi')).

Selectors akanyatsorongwa

Pane imwe nzira yokusarudza zvinhu muna JQuery, kureva - maererano akanyatsorongwa dzavo (ndiko, nhamba mumwe ari HTML-peji). Vakawanda vavo, saka isu kupa mbiri zvikuru nevanhu, "mwana" uye "muzukuru".

Muchiitiko chokutanga okunze vanosarudzwa, izvo zvakananga zvizvarwa (vana) ane vakapiwa Kufananidzira (tateguru). Somuenzaniso, kusarudza pezvokuvamba ndandanda mukirasi chiedza chiri mwana Nav list, ipapo unofanira kunyora: $ (Ul # Nav> li.light).

nyaya yechipiri - kupfuura zvavo. Pane anogona kusarudzwa uye zvisina kunanga vazukuru maatomu akafanana. Somuenzaniso, kusarudza Links mukati ndandanda Nav varayire: $ (Ul # Nav a).

Saka, muna JQuery zvinhu zvinogona kusarudzwa nenzira dzakasiyana-siyana achishandisa parameters akadai boka, ID, unhu, kugutsikana kana akanyatsorongwa kuti HTML-gwaro zvinhu.