JavaScript: ngwa atụ

Ọ bụrụ na ozugbo amaba n'ime nkenke syntax na semantics nke JavaScript arụmọrụ, mfe koodu ihe atụ ga-enyere iji ngwa ngwa ịmụta otú ka mma dynamism na arụmọrụ nke peeji nke.

JS - mmemme asụsụ "n'ime" nchọgharị. JavaScript nwere ọtụtụ ahụmahụ na-arụ ọrụ na peeji nke ọcha, na mbụ ngwọta na ubi nke ihe na-abara mmemme, "bụ ike" na-ekwurịta okwu na nkesa, n'ihi na ọtụtụ n'ime JavaScript code samples bụ ozugbo dị ka ịghọta na itinye.

General site onwe: mfe mmalite

Programming na nchọgharị ka na-eto eto, ma ngwa ngwa akwakọba a elu-edu na mbụ ahụmahụ. The syntax na semantics nke JavaScript natara n'aka-akpọ "nna nna", na akụkụ ndị ọrụ na uru nke syntax - kemgbe tupu internet mmemme asụsụ, karịsịa C / C ++, onwa.

Nchọgharị na JavaScript atụ, adịghị na-achọ ịghọta ozugbo mgbagha nke echiche nke ndị na-ede na arụmọrụ nke algọridim - a unpromising ọrụ, mma ilekwasị anya gị onwe gị onwe omume.

Nanị na-amalite na na njikọ onload handler na ozu na mkpado ma dee omenala "Hello" a nke oge a style "I`m njikere".

Ihe atụ ndị a na-egosi na JavaScript:

• na onload omume, ime mgbe page ibu na-kenyere a handler - GoPage () ọrụ;
• na peeji nke ibu, na management ọrụ na-enweta GoPage ();
• ihe ígwè okwu intercom na njikere ọrụ asụsụ, nke na-egosiputa a ozi dị na nchọgharị "Adị m njikere";
• Browser esenowo na-atụ anya mmeghachi omume.

The nkọwa na-akọwa omume na-emekarị ga-mere mgbe download page na-amalite ngụ oge.

Nnọọ adaba: JS na-anya na njikọ aka page ọcha. Ya mere, document.getElementById oku na-enye a njikọ ka a div na "scTimer" nchọpụta. Iji na-ewu dTimer.innerHTML = "ọ bụla nti HTML koodu", i nwere ike dynamically ịgbanwe ọdịnaya nke div.

Ọ ga karịsịa ntị ka njehie ahụ nke undesirability nke scripts na JavaScript. Ihe atụ nke a ka na-adịghị mma na ya pụta. The n'elu koodu kpọmkwem njikere ( 'm dịkwa njikere'), na-arụ ọrụ ọ na-adịghị. Na-egosi ụdị ọ bụla nke e nyere ahịrị kwere apostrophes: ma otu na abụọ, nke n'ime a ụzọ nke otu ụdị nwere ike ji mee naanị, ndị ọzọ na - dị ka ihe nnọchianya.

Na nke a, ọ ga e kpọmkwem, ma njikere ( "M na njikere"), na nche ( 'I`m njikere'), na nche ( 'm \' M njikere '), ma ọ bụ ndị ọzọ n'ịgwa.

Error na JS-koodu

Na mbụ bụ nchọgharị, na ụzọ nke esenowo ọ kwajuru peeji nke nke saịtị, wuru a DOM osisi nyeere JavaScript ọrụ: na-enye ya ohere nyochaa loaded page, initialize ya ọcha, omume ahụ maka, na jikọọ na-eme ka na kọntaktị na nkesa.

Inyocha JavaScript (atụ), ọ dị mkpa na ntị ka koodu debugging. Nke a na usoro na-esiwanye dara na Mmepụta. The nchọgharị na nke na-arụ ọrụ na-rụrụ, nwere ike gwa Abigel a ma ọ bụ ndị ọzọ debugging ngwaọrụ, ma ahụmahụ na-egosi na ịgbasochi na asụsụ syntax, mfe na correctness nke algọridim nwere a nnọọ ukwuu utịp ke nweta nke na-arụ ọrụ na-arụpụta.