JavaScript: Chikumbiro mienzaniso

Kana kwete pakarepo svetuka kupinda zvipfupi nemarongerwo uye semantics of JavaScript functionality, nyore remitemo mienzaniso kuchabatsira kuti nokukurumidza kudzidza kuvandudza dynamism uye kunyatsoshanda pamusoro mapeji.

JS - mutauro zvirongwa "mukati" Browser. JavaScript ane zvakawanda chiitiko kushanda peji okunze, chepakutanga zvingaitwa mune chinhu-zvinangwa zvirongwa, "anogona" kukurukurirana Server, nekuti vazhinji JavaScript remitemo ivhu havasi pakarepo kuwanika kunzwisisa uye kushandisa.

General kuburikidza private: kutanga nyore

Zvirongwa ari mubrowser achiri mudiki, asi nokukurumidza akazviunganidzira munhu yepamusoro uye yapakuvamba ruzivo. The nemarongerwo uye semantics of JavaScript kubva vanoda "madzitateguru", uye muchidimbu kuti functionality uye kushanda kunoita nemarongerwo - kubvira pre-internet zvirongwa mitauro, kunyanya C / C ++, Pascal.

Browsing pamwe JavaScript mienzaniso, regai kutsvaka pakarepo kunzwisisa pfungwa nemafungiro hachishandi uye functionality of algorithms - ichi unpromising basa, nani pfungwa dzenyu private tsika.

Simply kutanga kubatana onload Handler pamusoro muviri Tag uye nyora chinyakare "Hello" mune ano manyorerwo "I`m vakagadzirira".

Mienzaniso iyi inoratidza muna JavaScript:

• ari onload chiitiko, kuitika mushure peji mutoro iri hurukuro Handler - GoPage () shanda;
• peji makaremerwa, uye kutarisirwa kushanda anogamuchira GoPage ();
• neintercom akangwarira kushanda mutauro, iyo anoratidza mashoko ari mubrowser "Ini ndakagadzirira";
• Browser muenzi anotarisira kuita.

The komendari rinotsanangura zviito kuti kazhinji anofanira kuitwa pashure Download peji uye tatanga timer.

Very nyore: JS hwakada chaizvo chokuita kuti peji zvinhu. Saka, document.getElementById kudanwa inopa kubatana kuti div ne "scTimer" identifier. Uchishandisa kuvaka dTimer.innerHTML = "chero chikonzero HTML bumbiro", unogona dynamically kushandura zviri div.

Zvinofanira kunyanya kuteerera kukanganisa mu muviri undesirability pakati mumanyoro muna JavaScript. Mienzaniso iyi kukonzera migumisiro yakaipa. pamusoro Mubumbiro The wainyatsotaura akangwarira ( 'Ndakagadzirira'), uye basa hazvina. Kuratidza chero mitsara mhando akabvumira apostrophes: Single uye kaviri, sezvamakaropafadzwa mukati peya imwe mhando zvingashandiswa oga, vamwe - sechiratidzo.

Muchiitiko ichi chinofanira kunge wainyatsotaura, kana ( "Ini ndakagadzirira"), makagadzirira ( 'I`m vakagadzirira'), wakangwarira ( 'I \' that m vakagadzirira '), kana zvimwe anofambidzana takamuka.

Error muna Nh-bumbiro

Pakutanga kwaiva Browser, nokutanga yacho mushanyi iye akatakudza peji kwenzvimbo, akavaka Dom muti uye zvakaita JavaScript mashandiro: kumupa mukana kuongorora monica peji, initialize zvinhu zvayo, chiitiko handlers, uye batanidza kuti kuonana navanhu Server.

Kuongorora JavaScript (mienzaniso), zvinokosha kuti unyatsoteerera bumbiro debugging. nzira Izvi kuramba weveta yokuvaka. The Browser umo basa rinoitwa, anogona zvamaronga izvi kana zvimwe debugging maturusi asi zvinoratidza kuti kunyatsotevedza mutauro nemarongerwo, kudekara uye rakarurama algorithm vane kukuru zvainoita kubudirira rokuvhiya zvabuda.