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>> SPIKA 1: Sasa katika mfano kwamba mwisho,
kukumbuka kwamba sisi yamejaa baadhi

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JavaScript code ndani ya HTML yangu,
hasa, ndani ya thamani ya

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sifa aitwaye On Kuwasilisha
kwa kuwa tag aina.

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Sasa kwa ajili ya kurasa ndogo, hii
si kama mpango mkubwa.

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Lakini kama ukurasa wa mtandao anapata tena na zaidi
tata, tu kuweka yako

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JavaScript code hapa na pale ndani ya
ya thamani ya sifa ni si

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kubuni bora.

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Bora kama sisi sababu ya kuwa nje na
angalau kuweka ndani ya

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tag script serikali kuu.

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>> Jinsi ya kufanya hivyo?

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Naam hebu kurudi fomu tag yangu na
kwanza kufuta sifa hii na wake

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thamani kabisa.

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Kisha up hapa, badala ya kufafanua
kazi kuitwa Nisalimieni, hebu hutegemea

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mstari wa kificho kwamba hatimaye sisi
bado wanataka kutekeleza na kuchukua nafasi ya

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Kazi Nisalimieni kama ifuatavyo.

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Document.get Element By ID
unquote demo kunukuu -

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ambapo demo, kukumbuka, ni ya kipekee
kitambulisho kwa aina yenyewe -

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dot juu ya kuwasilisha, ambayo kukumbuka ni jina
ya tukio handler katika ambayo

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sisi ni nia.

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Na hebu hawawajui kwamba kuwasilisha handler
thamani hiyo ni kweli

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kazi yenyewe.

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>> Sasa taarifa kwamba mimi si kweli
wito kazi hapa.

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Mimi badala kufafanua majina,
inayojulikana kama lambda kazi,

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na kubainisha kati ya braces haya curly
kundi la kificho kwamba lazima

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kweli ni lazima ifanyike.

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Hasa, kificho kwamba Ningependa
kutekeleza ni kwamba line kuwa nilikuwa

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kabla, na kisha hebu kuongeza kuwa
kurudi uongo ili fomu hii sio

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hatimaye kuwasilishwa kwa mwisho kijijini mtandao
server katika njia ya jadi.

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>> Hebu sasa ila faili hili, kufungua it up
katika browser, na kuona nini kinatokea.

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http://localhost/dom-1.html.

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Hebu sasa aina kwa jina langu,
Daudi, Kuwasilisha.

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Na kitu inaonekana kuwa kilichotokea
ila URL ya ukurasa wangu inaonekana

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yamebadilika kana kwamba fomu ilikuwa
kweli kuwasilishwa kwa faili moja.

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>> Sasa kwa nini huenda kuwa ni nani?

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Naam, mimi haja ya baadhi ya maelezo zaidi.

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Basi hebu kwenda mbele na kufungua Chrome ya
Developer Vyombo vya ili niweze kweli

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kuangalia console dirisha kuona
kama mimi tumefanya kitu kibaya.

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Mimi unaweza kupata kwamba kupitia
michache ya njia.

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Moja ambayo ni ya kupitia orodha hii hapa,
kisha chini ya Tools, kisha chini ya

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Developer vifaa.

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>> Na taarifa hapa katika tab Console,
kuna uncaught aina makosa, hawezi

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kuweka mali ya kuwasilisha wa null.

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Sasa kwa nini huenda kuwa ni nani?

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Vizuri nyuma katika chanzo code yangu hapa, taarifa
kwamba kuwasilisha nadhani ni

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mali ya hiki ambao
kitambulisho kipekee ni demo.

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hiki, tena, ni
node katika mti.

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>> Hivyo inaonekana kwamba browser yangu haina
kufikiri kwamba hiki

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au node ipo bado.

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Na kwa kweli, haina.

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Kumbuka kwamba ukurasa wa mtandao ni parsed au kusoma
na mtandao browser, juu hadi chini,

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kushoto na kulia.

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Na hivyo wakati JavaScript code ni
yaliyojitokeza, kwa kawaida, ni kunyongwa

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haki ya mbali.

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>> Lakini katika kesi hii, sisi si hata wamezipata
bado sehemu ya dom,

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HTML, ambayo kwamba fomu na ya kipekee
kitambulisho demo imekuwa alisema.

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Na hivyo sisi ni kujaribu kutekeleza yangu
JavaScript code kabla ya node hata

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ipo katika mti ambayo, bila shaka, ni
tatizo kwa sababu wakati huo, kwa hakika,

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hiki yenyewe itakuwa null
katika hatua hiyo kwa wakati.

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>> Hivyo ni jinsi ya kurekebisha?

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Pamoja na sisi kuwa wanandoa wa ufumbuzi.

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Lakini hebu jaribu rahisi na kuhamia
script tag yangu kutoka kichwa

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tag mwili wangu, lakini hasa, upande wa
chini ya mwili ukurasa wangu ili

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kwamba ni chini ya nodes
na maswali.

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Hasa, hebu kuonyesha na kupunguza
tag wazi na tag karibu kwa script

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na kuhama kuzuia kwamba nzima ya maadili ya
chini ya file hapa.

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>> Sasa hii si lazima safi
kubuni, lakini angalau itakuwa

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kutekeleza ili haki ya shughuli.

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Hebu kuokoa faili na
Reload katika browser yangu.

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Hebu upya ukurasa, re-pembejeo jina langu,
na huko, Hello David ni nyuma.

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