{"id":264273,"date":"2023-09-25T23:45:10","date_gmt":"2023-09-25T16:45:10","guid":{"rendered":"https:\/\/hoanghamobile.com\/tin-tuc\/?p=264273"},"modified":"2023-09-25T23:45:10","modified_gmt":"2023-09-25T16:45:10","slug":"javascript","status":"publish","type":"post","link":"https:\/\/hoanghamobile.com\/tin-tuc\/javascript\/","title":{"rendered":"JavaScript l\u00e0 g\u00ec? C\u00e1ch b\u1eadt JavaScript tr\u00ean \u0111i\u1ec7n tho\u1ea1i"},"content":{"rendered":"

JavaScript<\/strong> l\u00e0 ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh kh\u00f4ng th\u1ec3 thi\u1ebfu trong th\u1ebf gi\u1edbi web, \u0111\u00f3ng vai tr\u00f2 quan tr\u1ecdng trong vi\u1ec7c x\u00e2y d\u1ef1ng v\u00e0 t\u1ed1i \u01b0u h\u00f3a tr\u1ea3i nghi\u1ec7m ng\u01b0\u1eddi d\u00f9ng. \u0110\u1ed1i v\u1edbi ng\u01b0\u1eddi m\u1edbi b\u1eaft \u0111\u1ea7u, vi\u1ec7c n\u1eafm v\u1eefng ki\u1ebfn th\u1ee9c v\u1ec1 ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh n\u00e0y l\u00e0 b\u01b0\u1edbc \u0111\u1ec7m quan tr\u1ecdng \u0111\u1ec3 tr\u1edf th\u00e0nh l\u1eadp tr\u00ecnh vi\u00ean web chuy\u00ean nghi\u1ec7p. N\u1ebfu b\u1ea1n \u0111ang t\u00ecm hi\u1ec3u v\u1ec1 JS th\u00ec b\u00e0i vi\u1ebft n\u00e0y s\u1ebd l\u00e0 l\u1ef1a ch\u1ecdn ph\u00f9 h\u1ee3p.<\/p>\n

\u0110\u1ecbnh ngh\u0129a JavaScript<\/h2>\n

JavaScript \u0111\u01b0\u1ee3c ra \u0111\u1eddi v\u00e0o n\u0103m 1995 b\u1edfi Brendan Eich t\u1ea1i c\u00f4ng ty Netscape Communications Corporation. Ban \u0111\u1ea7u, JS \u0111\u01b0\u1ee3c ph\u00e1t tri\u1ec3n v\u1edbi t\u00ean m\u00e3 Mocha, sau \u0111\u1ed5i th\u00e0nh LiveScript, v\u00e0 cu\u1ed1i c\u00f9ng l\u00e0 JavaScript. Ng\u00f4n ng\u1eef n\u00e0y \u0111\u00e3 tr\u1ea3i qua nhi\u1ec1u phi\u00ean b\u1ea3n v\u00e0 hi\u1ec7n t\u1ea1i \u0111\u00e3 tr\u1edf th\u00e0nh m\u1ed9t trong nh\u1eefng ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh quan tr\u1ecdng v\u00e0 ph\u1ed5 bi\u1ebfn nh\u1ea5t tr\u00ean th\u1ebf gi\u1edbi.<\/p>\n

\"javascript\"<\/picture><\/p>\n

JS n\u1ed5i b\u1eadt v\u1edbi kh\u1ea3 n\u0103ng t\u01b0\u01a1ng t\u00e1c cao, t\u1ea1o ra tr\u1ea3i nghi\u1ec7m ng\u01b0\u1eddi d\u00f9ng \u0111\u1ed9ng v\u00e0 phong ph\u00fa. N\u00f3 cho ph\u00e9p l\u1eadp tr\u00ecnh vi\u00ean th\u1ef1c hi\u1ec7n c\u00e1c thao t\u00e1c DOM, x\u1eed l\u00fd s\u1ef1 ki\u1ec7n v\u00e0 t\u01b0\u01a1ng t\u00e1c AJAX, l\u00e0m cho trang web tr\u1edf n\u00ean linh ho\u1ea1t v\u00e0 s\u1ed1ng \u0111\u1ed9ng. Tuy nhi\u00ean, JavaScript c\u0169ng g\u1eb7p ph\u1ea3i m\u1ed9t s\u1ed1 v\u1ea5n \u0111\u1ec1 nh\u01b0 t\u00ednh kh\u00f4ng an to\u00e0n, s\u1ef1 kh\u00f4ng nh\u1ea5t qu\u00e1n gi\u1eefa c\u00e1c tr\u00ecnh duy\u1ec7t v\u00e0 t\u1ed1c \u0111\u1ed9 ch\u1ea1y c\u00f3 th\u1ec3 ch\u1eadm n\u1ebfu code ph\u1ee9c t\u1ea1p.<\/p>\n

T\u1ea7m quan tr\u1ecdng c\u1ee7a JS<\/h2>\n

JavaScript \u0111\u01b0\u1ee3c bi\u1ebft \u0111\u1ebfn l\u00e0 m\u1ed9t ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh \u0111a n\u0103ng v\u00e0 linh ho\u1ea1t, c\u00f3 nhi\u1ec7m v\u1ee5 quan tr\u1ecdng trong vi\u1ec7c l\u00e0m s\u1ed1ng \u0111\u1ed9ng c\u00e1c trang web v\u00e0 \u1ee9ng d\u1ee5ng. M\u1eb7t tr\u01b0\u1edbc, hay c\u00f2n g\u1ecdi l\u00e0 front-end, JS c\u00f3 kh\u1ea3 n\u0103ng thay \u0111\u1ed5i n\u1ed9i dung HTML, \u0111i\u1ec1u ch\u1ec9nh layout CSS, v\u00e0 x\u1eed l\u00fd s\u1ef1 ki\u1ec7n t\u1eeb ng\u01b0\u1eddi d\u00f9ng nh\u01b0 c\u00e1c click chu\u1ed9t \u0111\u1ec3 mang \u0111\u1ebfn tr\u1ea3i nghi\u1ec7m t\u01b0\u01a1ng t\u00e1c v\u00e0 \u0111\u00e1p \u1ee9ng nhanh nh\u1eb9n.<\/p>\n

M\u1ed9t v\u00ed d\u1ee5 \u0111i\u1ec3n h\u00ecnh v\u1ec1 vi\u1ec7c s\u1eed d\u1ee5ng JS \u1edf ph\u00eda front-end l\u00e0 khi b\u1ea1n truy c\u1eadp m\u1ed9t trang web v\u00e0 click v\u00e0o m\u1ed9t n\u00fat. L\u00fac n\u00e0y, JS s\u1ebd x\u1eed l\u00fd s\u1ef1 ki\u1ec7n n\u00e0y, th\u1ef1c hi\u1ec7n c\u00e1c h\u00e0m t\u01b0\u01a1ng \u1ee9ng v\u00e0 c\u1eadp nh\u1eadt giao di\u1ec7n ng\u01b0\u1eddi d\u00f9ng m\u00e0 kh\u00f4ng c\u1ea7n t\u1ea3i l\u1ea1i trang.<\/p>\n

\"javascript-1\"<\/picture><\/p>\n

Ph\u00eda sau h\u1eadu tr\u01b0\u1eddng, hay c\u00f2n g\u1ecdi l\u00e0 back-end, JavaScript c\u0169ng kh\u00f4ng k\u00e9m ph\u1ea7n quan tr\u1ecdng. Ng\u00f4n ng\u1eef n\u00e0y \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 x\u00e2y d\u1ef1ng c\u00e1c \u1ee9ng d\u1ee5ng m\u00e1y ch\u1ee7, x\u1eed l\u00fd d\u1eef li\u1ec7u, v\u00e0 t\u01b0\u01a1ng t\u00e1c v\u1edbi c\u01a1 s\u1edf d\u1eef li\u1ec7u. V\u1edbi Node.js, m\u1ed9t m\u00f4i tr\u01b0\u1eddng ch\u1ea1y JS, l\u1eadp tr\u00ecnh vi\u00ean c\u00f3 kh\u1ea3 n\u0103ng vi\u1ebft m\u00e3 x\u1eed l\u00fd tr\u00ean m\u00e1y ch\u1ee7, x\u1eed l\u00fd c\u00e1c y\u00eau c\u1ea7u v\u00e0 tr\u1ea3 d\u1eef li\u1ec7u v\u1ec1 ph\u00eda client.<\/p>\n

Th\u1ef1c t\u1ebf, JS l\u00e0 m\u1ed9t trong nh\u1eefng c\u00f4ng c\u1ee5 kh\u00f4ng th\u1ec3 thi\u1ebfu trong chi\u1ebfc c\u1ed1c c\u00f4ng c\u1ee5 c\u1ee7a l\u1eadp tr\u00ecnh vi\u00ean web, gi\u00fap h\u1ecd x\u00e2y d\u1ef1ng n\u00ean c\u00e1c \u1ee9ng d\u1ee5ng web \u0111\u1ea7y m\u00e0u s\u1eafc, t\u00ednh n\u0103ng v\u00e0 s\u00e1ng t\u1ea1o. T\u1eeb vi\u1ec7c thay \u0111\u1ed5i n\u1ed9i dung trang web theo th\u1eddi gian th\u1ef1c, t\u1ea1o ra c\u00e1c hi\u1ec7u \u1ee9ng \u0111\u1ed3 h\u1ecda, \u0111\u1ebfn vi\u1ec7c x\u00e2y d\u1ef1ng c\u00e1c \u1ee9ng d\u1ee5ng m\u00e1y ch\u1ee7 m\u1ea1nh m\u1ebd v\u00e0 linh \u0111\u1ed9ng, JS \u0111\u1ec1u c\u00f3 th\u1ec3 \u0111\u00e1p \u1ee9ng.<\/p>\n

C\u01a1 b\u1ea3n v\u1ec1 JS<\/h2>\n

Tr\u00ean th\u1ef1c t\u1ebf, JS l\u00e0 m\u1ed9t ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh t\u01b0\u01a1ng \u0111\u1ed1i d\u1ec5 ti\u1ebfp c\u1eadn, \u0111\u1eb7c bi\u1ec7t l\u00e0 \u0111\u1ed1i v\u1edbi nh\u1eefng l\u1eadp tr\u00ecnh vi\u00ean \u0111\u00e3 c\u00f3 ki\u1ebfn th\u1ee9c v\u1ec1 c\u00e1c ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh kh\u00e1c. D\u01b0\u1edbi \u0111\u00e2y l\u00e0 c\u00e1c \u0111\u1eb7c \u0111i\u1ec3m s\u01a1 l\u01b0\u1ee3c v\u1ec1 JS m\u00e0 b\u1ea1n n\u00ean bi\u1ebft.<\/p>\n

C\u1ea5u tr\u00fac v\u00e0 C\u00fa ph\u00e1p<\/h3>\n

Bi\u1ebfn v\u00e0 ki\u1ec3u d\u1eef li\u1ec7u<\/strong><\/p>\n

Trong JavaScript, bi\u1ebfn l\u00e0 n\u01a1i l\u01b0u tr\u1eef d\u1eef li\u1ec7u, v\u00e0 ch\u00fang c\u00f3 th\u1ec3 ch\u1ee9a c\u00e1c gi\u00e1 tr\u1ecb nh\u01b0 chu\u1ed7i, s\u1ed1, m\u1ea3ng, \u0111\u1ed1i t\u01b0\u1ee3ng, v\u00e0 h\u00e0m. \u0110\u1ec3 khai b\u00e1o bi\u1ebfn, ch\u00fang ta s\u1eed d\u1ee5ng t\u1eeb kh\u00f3a var, let ho\u1eb7c const. JS cung c\u1ea5p nhi\u1ec1u ki\u1ec3u d\u1eef li\u1ec7u nh\u01b0 string, number, boolean, object, null, v\u00e0 undefined, gi\u00fap l\u1eadp tr\u00ecnh vi\u00ean linh ho\u1ea1t trong vi\u1ec7c x\u1eed l\u00fd d\u1eef li\u1ec7u.<\/p>\n

\"javascript-2\"<\/picture><\/p>\n

C\u00e2u l\u1ec7nh \u0111i\u1ec1u ki\u1ec7n v\u00e0 v\u00f2ng l\u1eb7p<\/strong><\/p>\n

JS s\u1eed d\u1ee5ng c\u00e1c c\u00e2u l\u1ec7nh \u0111i\u1ec1u ki\u1ec7n nh\u01b0 if, else if, v\u00e0 else \u0111\u1ec3 ki\u1ec3m tra \u0111i\u1ec1u ki\u1ec7n v\u00e0 th\u1ef1c thi m\u00e3 code t\u01b0\u01a1ng \u1ee9ng. V\u1ec1 v\u00f2ng l\u1eb7p, JavaScript cung c\u1ea5p c\u00e1c c\u1ea5u tr\u00fac nh\u01b0 for, while, v\u00e0 do…while, gi\u00fap l\u1eb7p qua c\u00e1c kh\u1ed1i m\u00e3 v\u00e0 th\u1ef1c hi\u1ec7n c\u00e1c t\u00e1c v\u1ee5 l\u1eb7p \u0111i l\u1eb7p l\u1ea1i.<\/p>\n

C\u00e1ch JavaScript ho\u1ea1t \u0111\u1ed9ng tr\u00ean tr\u00ecnh duy\u1ec7t<\/h3>\n

DOM v\u00e0 BOM<\/strong><\/p>\n

JS t\u01b0\u01a1ng t\u00e1c v\u1edbi trang web th\u00f4ng qua Document Object Model (DOM) v\u00e0 Browser Object Model (BOM). DOM cho ph\u00e9p JS \u0111\u1ecdc v\u00e0 thay \u0111\u1ed5i n\u1ed9i dung, c\u1ea5u tr\u00fac c\u1ee7a m\u1ed9t trang web, c\u00f2n BOM cho ph\u00e9p JS t\u01b0\u01a1ng t\u00e1c v\u1edbi tr\u00ecnh duy\u1ec7t, nh\u01b0 thay \u0111\u1ed5i k\u00edch th\u01b0\u1edbc c\u1eeda s\u1ed5, \u0111i\u1ec1u h\u01b0\u1edbng, ho\u1eb7c hi\u1ec3n th\u1ecb th\u00f4ng b\u00e1o alert.<\/p>\n

\"javascript-3\"<\/picture><\/p>\n

Event Handling<\/strong><\/p>\n

JavaScript s\u1eed d\u1ee5ng Event Handling \u0111\u1ec3 t\u1ea1o ra c\u00e1c \u1ee9ng d\u1ee5ng \u0111\u1ed9ng v\u00e0 t\u01b0\u01a1ng t\u00e1c. Khi ng\u01b0\u1eddi d\u00f9ng th\u1ef1c hi\u1ec7n m\u1ed9t h\u00e0nh \u0111\u1ed9ng n\u00e0o \u0111\u00f3 tr\u00ean trang web, nh\u01b0 click chu\u1ed9t, g\u00f5 ph\u00edm, hay k\u00e9o chu\u1ed9t, JS c\u00f3 th\u1ec3 b\u1eaft l\u1ea5y s\u1ef1 ki\u1ec7n \u0111\u00f3 v\u00e0 th\u1ef1c hi\u1ec7n c\u00e1c h\u00e0m t\u01b0\u01a1ng \u1ee9ng \u0111\u1ec3 t\u1ea1o ra hi\u1ec7u \u1ee9ng ho\u1eb7c thay \u0111\u1ed5i n\u1ed9i dung trang web.<\/p>\n

C\u00e1ch b\u1eadt JavaScript tr\u00ean \u0111i\u1ec7n tho\u1ea1i<\/h2>\n

V\u1ec1 c\u01a1 b\u1ea3n, c\u00f3 kh\u00e1 nhi\u1ec1u c\u00e1ch \u0111\u1ec3 b\u1eadt JS tr\u00ean \u0111i\u1ec7n tho\u1ea1i \u0111\u1ec3 ph\u1ee5c v\u1ee5 cho m\u1ed9t s\u1ed1 nhu c\u1ea7u c\u1ee5 th\u1ec3 c\u1ee7a ng\u01b0\u1eddi d\u00f9ng, \u0111i\u1ec3n h\u00ecnh nh\u01b0:<\/p>\n

B\u1eadt JS tr\u00ean Android<\/h3>\n

M\u1edf tr\u00ecnh duy\u1ec7t Chrome<\/strong><\/p>\n

Truy c\u1eadp v\u00e0o Settings: M\u1edf tr\u00ecnh duy\u1ec7t Chrome, t\u00ecm v\u00e0 ch\u1ecdn bi\u1ec3u t\u01b0\u1ee3ng ba ch\u1ea5m \u1edf g\u00f3c tr\u00ean b\u00ean ph\u1ea3i m\u00e0n h\u00ecnh \u0111\u1ec3 truy c\u1eadp menu, sau \u0111\u00f3 ch\u1ecdn \u201cSettings\u201d.<\/p>\n

\"javascript-cach-bat\"<\/picture><\/p>\n

Ch\u1ecdn Site Settings v\u00e0 k\u00edch ho\u1ea1t JavaScript: Trong ph\u1ea7n \u201cSettings\u201d, cu\u1ed9n xu\u1ed1ng v\u00e0 ch\u1ecdn \u201cSite Settings\u201d. T\u00ecm v\u00e0 ch\u1ecdn \u201cJavaScript\u201d sau \u0111\u00f3 k\u00edch ho\u1ea1t ch\u1ee9c n\u0103ng n\u00e0y b\u1eb1ng c\u00e1ch chuy\u1ec3n n\u00fat t\u1eeb OFF sang ON.<\/p>\n

\"javascript-cach-bat-1\"<\/picture><\/p>\n

M\u1edf tr\u00ecnh duy\u1ec7t Firefox<\/strong><\/p>\n

Truy c\u1eadp v\u00e0o Settings: M\u1edf tr\u00ecnh duy\u1ec7t Firefox, ch\u1ecdn menu (th\u01b0\u1eddng l\u00e0 ba d\u1ea5u g\u1ea1ch ngang) v\u00e0 sau \u0111\u00f3 ch\u1ecdn \u201cSettings\u201d.<\/p>\n

Ch\u1ecdn Enable JavaScript: Trong ph\u1ea7n \u201cSettings\u201d, t\u00ecm v\u00e0 ch\u1ecdn ph\u1ea7n \u201cJavaScript\u201d v\u00e0 \u0111\u1ea3m b\u1ea3o r\u1eb1ng n\u00f3 \u0111\u00e3 \u0111\u01b0\u1ee3c k\u00edch ho\u1ea1t.<\/p>\n

B\u1eadt JS tr\u00ean iOS<\/h3>\n

M\u1edf tr\u00ecnh duy\u1ec7t Safari<\/strong><\/p>\n

Truy c\u1eadp v\u00e0o Settings: Tr\u00ean m\u00e0n h\u00ecnh ch\u00ednh c\u1ee7a thi\u1ebft b\u1ecb iOS, m\u1edf \u1ee9ng d\u1ee5ng \u201cSettings\u201d, cu\u1ed9n xu\u1ed1ng v\u00e0 ch\u1ecdn \u201cSafari\u201d.<\/p>\n

Ch\u1ecdn Safari v\u00e0 k\u00edch ho\u1ea1t JS: Cu\u1ed9n xu\u1ed1ng t\u00ecm \u0111\u1ebfn ph\u1ea7n \u201cAdvanced\u201d, ch\u1ecdn v\u00e0 \u0111\u1ea3m b\u1ea3o r\u1eb1ng t\u00f9y ch\u1ecdn \u201cJavaScript\u201d \u0111\u00e3 \u0111\u01b0\u1ee3c k\u00edch ho\u1ea1t.<\/p>\n

\"javascript-cach-bat-2\"<\/picture><\/p>\n

Ki\u1ec3m tra xem JavaScript \u0111\u00e3 \u0111\u01b0\u1ee3c b\u1eadt ch\u01b0a<\/h3>\n

C\u00e1ch ki\u1ec3m tra tr\u00ean tr\u00ecnh duy\u1ec7t<\/strong><\/p>\n

Sau khi \u0111\u00e3 k\u00edch ho\u1ea1t JavaScript, b\u1ea1n c\u00f3 th\u1ec3 m\u1edf m\u1ed9t trang web c\u00f3 s\u1eed d\u1ee5ng JS \u0111\u1ec3 ki\u1ec3m tra xem n\u00f3 \u0111\u00e3 ho\u1ea1t \u0111\u1ed9ng ch\u01b0a, ho\u1eb7c t\u00ecm ki\u1ebfm tr\u1ef1c tuy\u1ebfn v\u1edbi t\u1eeb kh\u00f3a \u201cIs JavaScript enabled\u201d v\u00e0 truy c\u1eadp m\u1ed9t trong s\u1ed1 c\u00e1c trang web ki\u1ec3m tra JS.<\/p>\n

S\u1eed d\u1ee5ng trang web ki\u1ec3m tra<\/strong><\/p>\n

C\u00f3 nhi\u1ec1u trang web c\u00f3 th\u1ec3 ki\u1ec3m tra xem JS \u0111\u00e3 \u0111\u01b0\u1ee3c b\u1eadt ch\u01b0a tr\u00ean tr\u00ecnh duy\u1ec7t c\u1ee7a b\u1ea1n. M\u1ed9t trong nh\u1eefng trang web ph\u1ed5 bi\u1ebfn v\u00e0 \u0111\u00e1ng tin c\u1eady l\u00e0 enable-javascript.com. B\u1ea1n ch\u1ec9 c\u1ea7n truy c\u1eadp trang web v\u00e0 theo d\u00f5i h\u01b0\u1edbng d\u1eabn \u0111\u1ec3 ki\u1ec3m tra.<\/p>\n

\"javascript-cach-bat-kiem-tra\"<\/picture><\/p>\n

Nh\u00ecn chung, vi\u1ec7c b\u1eadt JavaScript tr\u00ean \u0111i\u1ec7n tho\u1ea1i l\u00e0 quy tr\u00ecnh \u0111\u01a1n gi\u1ea3n nh\u01b0ng quan tr\u1ecdng \u0111\u1ec3 t\u1eadn h\u01b0\u1edfng \u0111\u1ea7y \u0111\u1ee7 n\u1ed9i dung v\u00e0 ch\u1ee9c n\u0103ng c\u1ee7a c\u00e1c trang web. B\u1eb1ng c\u00e1ch theo d\u00f5i c\u00e1c b\u01b0\u1edbc tr\u00ean v\u00e0 ki\u1ec3m tra c\u1ea9n th\u1eadn, b\u1ea1n c\u00f3 th\u1ec3 \u0111\u1ea3m b\u1ea3o r\u1eb1ng JS \u0111\u00e3 \u0111\u01b0\u1ee3c k\u00edch ho\u1ea1t th\u00e0nh c\u00f4ng tr\u00ean thi\u1ebft b\u1ecb c\u1ee7a m\u00ecnh.<\/p>\n

\u01afu \u0111i\u1ec3m v\u00e0 nh\u01b0\u1ee3c \u0111i\u1ec3m khi b\u1eadt JavaScript tr\u00ean \u0111i\u1ec7n tho\u1ea1i<\/h2>\n

D\u01b0\u1edbi \u0111\u00e2y l\u00e0 \u01b0u v\u00e0 nh\u01b0\u1ee3c \u0111i\u1ec3m m\u00e0 b\u1ea1n n\u00ean quan t\u00e2m khi ti\u1ebfn h\u00e0nh b\u1eadt JS tr\u00ean thi\u1ebft b\u1ecb Android ho\u1eb7c iOS c\u1ee7a m\u00ecnh.<\/p>\n

\u01afu \u0111i\u1ec3m<\/h3>\n

Tr\u1ea3i nghi\u1ec7m web t\u1ed1t h\u01a1n<\/strong><\/p>\n

JavaScript \u0111em l\u1ea1i cho ng\u01b0\u1eddi d\u00f9ng tr\u1ea3i nghi\u1ec7m tr\u1ef1c tuy\u1ebfn \u0111\u1ed9ng v\u00e0 t\u01b0\u01a1ng t\u00e1c, v\u1edbi c\u00e1c t\u00ednh n\u0103ng nh\u01b0 sliders, pop-ups, forms \u0111\u1ed9ng v\u00e0 nhi\u1ec1u hi\u1ec7u \u1ee9ng kh\u00e1c. Khi JavaScript \u0111\u01b0\u1ee3c k\u00edch ho\u1ea1t, trang web tr\u1edf n\u00ean s\u1ed1ng \u0111\u1ed9ng v\u00e0 th\u00fa v\u1ecb h\u01a1n, t\u0103ng s\u1ef1 h\u00e0i l\u00f2ng v\u00e0 tham gia c\u1ee7a ng\u01b0\u1eddi d\u00f9ng.<\/p>\n

\"javascript-uu-diem\"<\/picture><\/p>\n

Ch\u1ee9c n\u0103ng trang web \u0111a d\u1ea1ng<\/strong><\/p>\n

JavaScript m\u1edf r\u1ed9ng kh\u1ea3 n\u0103ng c\u1ee7a trang web b\u1eb1ng c\u00e1ch th\u00eam v\u00e0o c\u00e1c ch\u1ee9c n\u0103ng \u0111a d\u1ea1ng nh\u01b0 x\u00e1c th\u1ef1c form, t\u01b0\u01a1ng t\u00e1c AJAX, animation, v\u00e0 th\u1eadm ch\u00ed l\u00e0 ch\u01a1i game tr\u1ef1c tuy\u1ebfn. \u0110i\u1ec1u n\u00e0y gi\u00fap ng\u01b0\u1eddi d\u00f9ng ti\u1ebfp c\u1eadn v\u00e0 s\u1eed d\u1ee5ng \u0111\u1ea7y \u0111\u1ee7 c\u00e1c d\u1ecbch v\u1ee5 v\u00e0 t\u00ednh n\u0103ng tr\u00ean trang web.<\/p>\n

Nh\u01b0\u1ee3c \u0111i\u1ec3m<\/h3>\n

An to\u00e0n b\u1ea3o m\u1eadt<\/strong><\/p>\n

M\u1ed9t trong nh\u1eefng lo l\u1eafng khi s\u1eed d\u1ee5ng JavaScript l\u00e0 v\u1ea5n \u0111\u1ec1 an to\u00e0n b\u1ea3o m\u1eadt. JavaScript c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 th\u1ef1c hi\u1ec7n c\u00e1c cu\u1ed9c t\u1ea5n c\u00f4ng cross-site scripting (XSS) ho\u1eb7c \u0111\u1ec3 theo d\u00f5i h\u00e0nh vi tr\u1ef1c tuy\u1ebfn c\u1ee7a ng\u01b0\u1eddi d\u00f9ng. Do \u0111\u00f3, ng\u01b0\u1eddi d\u00f9ng c\u1ea7n c\u1ea9n th\u1eadn v\u1edbi c\u00e1c trang web kh\u00f4ng an to\u00e0n v\u00e0 c\u00e2n nh\u1eafc vi\u1ec7c s\u1eed d\u1ee5ng c\u00e1c \u1ee9ng d\u1ee5ng b\u1ea3o m\u1eadt nh\u01b0 firewall hay antivirus.<\/p>\n

\"javascript-nhuoc-diem\"<\/picture><\/p>\n

Ti\u00eau th\u1ee5 t\u00e0i nguy\u00ean v\u00e0 d\u1eef li\u1ec7u<\/strong><\/p>\n

JavaScript c\u00f3 th\u1ec3 t\u0103ng vi\u1ec7c s\u1eed d\u1ee5ng t\u00e0i nguy\u00ean h\u1ec7 th\u1ed1ng v\u00e0 ti\u00eau th\u1ee5 d\u1eef li\u1ec7u di \u0111\u1ed9ng. C\u00e1c script ph\u1ee9c t\u1ea1p v\u00e0 nhi\u1ec1u ch\u1ee9c n\u0103ng c\u00f3 th\u1ec3 l\u00e0m ch\u1eadm t\u1ed1c \u0111\u1ed9 t\u1ea3i trang web v\u00e0 \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn hi\u1ec7u su\u1ea5t c\u1ee7a thi\u1ebft b\u1ecb, \u0111\u1eb7c bi\u1ec7t l\u00e0 v\u1edbi nh\u1eefng thi\u1ebft b\u1ecb c\u00f3 c\u1ea5u h\u00ecnh th\u1ea5p h\u01a1n. Ngo\u00e0i ra, vi\u1ec7c t\u1ea3i c\u00e1c file JS l\u1edbn c\u0169ng c\u00f3 th\u1ec3 ti\u00eau th\u1ee5 l\u01b0\u1ee3ng d\u1eef li\u1ec7u \u0111\u00e1ng k\u1ec3, l\u00e0m t\u0103ng chi ph\u00ed cho ng\u01b0\u1eddi d\u00f9ng di \u0111\u1ed9ng.<\/p>\n

C\u00f3 th\u1ec3 nh\u1eadn th\u1ea5y, JS mang l\u1ea1i nhi\u1ec1u l\u1ee3i \u00edch cho tr\u1ea3i nghi\u1ec7m tr\u1ef1c tuy\u1ebfn, nh\u01b0ng c\u0169ng \u0111\u1ec1 xu\u1ea5t m\u1ed9t s\u1ed1 r\u1ee7i ro v\u00e0 h\u1ea1n ch\u1ebf. Ng\u01b0\u1eddi d\u00f9ng c\u1ea7n c\u00e2n nh\u1eafc gi\u1eefa l\u1ee3i \u00edch v\u00e0 r\u1ee7i ro, v\u00e0 c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng c\u00e1c c\u00f4ng c\u1ee5 v\u00e0 thi\u1ebft l\u1eadp b\u1ea3o m\u1eadt \u0111\u1ec3 b\u1ea3o v\u1ec7 m\u00ecnh khi tr\u1ea3i nghi\u1ec7m web.<\/p>\n

C\u00e1c IDE ph\u1ed5 bi\u1ebfn c\u1ee7a JS<\/h2>\n

C\u00f4ng c\u1ee5 ph\u00e1t tri\u1ec3n JavaScript, c\u00f2n \u0111\u01b0\u1ee3c bi\u1ebft \u0111\u1ebfn v\u1edbi t\u00ean g\u1ecdi IDE (Integrated Development Environment), l\u00e0 n\u1ec1n t\u1ea3ng m\u00e0 l\u1eadp tr\u00ecnh vi\u00ean s\u1eed d\u1ee5ng \u0111\u1ec3 vi\u1ebft, ki\u1ec3m tra v\u00e0 chia s\u1ebb m\u00e3 ngu\u1ed3n JavaScript. C\u00e1c IDE n\u00e0y kh\u00f4ng ch\u1ec9 h\u1ed7 tr\u1ee3 JavaScript m\u00e0 c\u00f2n m\u1ed9t lo\u1ea1t c\u00e1c ng\u00f4n ng\u1eef kh\u00e1c nh\u01b0 HTML v\u00e0 CSS, gi\u00fap t\u1ea1o ra c\u00e1c trang web \u0111a d\u1ea1ng v\u00e0 ch\u1ee9c n\u0103ng.<\/p>\n

Visual Studio<\/strong><\/p>\n

L\u00e0 s\u1ea3n ph\u1ea9m c\u1ee7a Microsoft, Visual Studio l\u00e0m m\u01b0a l\u00e0m gi\u00f3 tr\u00ean th\u1ecb tr\u01b0\u1eddng v\u1edbi giao di\u1ec7n ng\u01b0\u1eddi d\u00f9ng th\u00e2n thi\u1ec7n v\u00e0 \u0111a d\u1ea1ng t\u00ednh n\u0103ng. Visual Studio kh\u00f4ng ch\u1ec9 h\u1ed7 tr\u1ee3 JavaScript, m\u00e0 c\u00f2n l\u00e0 n\u01a1i tri\u1ec3n khai m\u00e3 ngu\u1ed3n HTML v\u00e0 CSS, gi\u00fap l\u1eadp tr\u00ecnh vi\u00ean t\u1ea1o ra c\u00e1c trang web ch\u1ea5t l\u01b0\u1ee3ng v\u00e0 \u0111a d\u1ea1ng ch\u1ee9c n\u0103ng.<\/p>\n

\"javascript-ide\"<\/picture><\/p>\n

NotePad ++<\/strong><\/p>\n

NotePad ++ kh\u00f4ng ch\u1ec9 l\u00e0 m\u1ed9t ph\u1ea7n m\u1ec1m so\u1ea1n th\u1ea3o m\u00e3 ngu\u1ed3n m\u1edf, m\u00e0 c\u00f2n l\u00e0 c\u00f4ng c\u1ee5 quen thu\u1ed9c v\u00e0 \u0111\u01b0\u1ee3c \u01b0a chu\u1ed9ng trong gi\u1edbi l\u1eadp tr\u00ecnh. V\u1edbi kh\u1ea3 n\u0103ng l\u01b0u tr\u1eef v\u00e0 ch\u1ec9nh s\u1eeda code m\u1ed9t c\u00e1ch ti\u1ec7n l\u1ee3i v\u00e0 linh ho\u1ea1t, NotePad ++ tr\u1edf th\u00e0nh l\u1ef1a ch\u1ecdn kh\u00f4ng th\u1ec3 thi\u1ebfu cho nhi\u1ec1u nh\u00e0 ph\u00e1t tri\u1ec3n.<\/p>\n

Google Cloud Shell<\/strong>:<\/p>\n

Google Cloud Shell, v\u1edbi s\u1ee9c m\u1ea1nh c\u1ee7a Google \u0111\u1eb1ng sau l\u00e0 m\u1ed9t c\u00f4ng c\u1ee5 ph\u00e1t tri\u1ec3n tr\u1ef1c tuy\u1ebfn \u1ea5n t\u01b0\u1ee3ng. N\u00f3 kh\u00f4ng ch\u1ec9 cung c\u1ea5p m\u00e1y \u1ea3o m\u1ea1nh m\u1ebd v\u00e0 d\u1eef li\u1ec7u l\u01b0u tr\u1eef l\u1edbn, m\u00e0 c\u00f2n gi\u00fap l\u1eadp tr\u00ecnh vi\u00ean c\u00f3 th\u1ec3 tri\u1ec3n khai v\u00e0 th\u1eed nghi\u1ec7m m\u00e3 JavaScript m\u1ed9t c\u00e1ch ti\u1ec7n l\u1ee3i v\u00e0 d\u1ec5 d\u00e0ng nh\u1ea5t.<\/p>\n

\"javascript-ide-1\"<\/picture><\/p>\n

Codetable<\/strong><\/p>\n

\u0110\u1ebfn t\u1eeb HackerEarth, Codetable l\u00e0 l\u1ef1a ch\u1ecdn ho\u00e0n h\u1ea3o cho nh\u1eefng ng\u01b0\u1eddi m\u1edbi b\u1eaft \u0111\u1ea7u con \u0111\u01b0\u1eddng l\u1eadp tr\u00ecnh. Cung c\u1ea5p m\u1ed9t s\u1ef1 hi\u1ec3u bi\u1ebft c\u01a1 b\u1ea3n v\u00e0 h\u1ed7 tr\u1ee3 nhi\u1ec1u ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh, Codetable l\u00e0 b\u01b0\u1edbc \u0111\u1ec7m v\u1eefng ch\u1eafc cho s\u1ef1 ph\u00e1t tri\u1ec3n c\u1ee7a l\u1eadp tr\u00ecnh vi\u00ean.<\/p>\n

T\u1ea1m k\u1ebft<\/h2>\n

Vi\u1ec7c hi\u1ec3u r\u00f5 c\u1ea5u tr\u00fac v\u00e0 c\u00fa ph\u00e1p c\u1ee7a JavaScript, c\u00f9ng v\u1edbi c\u00e1ch n\u00f3 t\u01b0\u01a1ng t\u00e1c v\u1edbi tr\u00ecnh duy\u1ec7t v\u00e0 trang web, l\u00e0 n\u1ec1n t\u1ea3ng quan tr\u1ecdng \u0111\u1ec3 tr\u1edf th\u00e0nh m\u1ed9t l\u1eadp tr\u00ecnh vi\u00ean JS gi\u1ecfi. Qua \u0111\u00f3, b\u1ea1n c\u00f3 th\u1ec3 t\u1ea1o ra c\u00e1c \u1ee9ng d\u1ee5ng web \u0111\u1ed9ng, s\u00e1ng t\u1ea1o v\u00e0 th\u00e2n thi\u1ec7n v\u1edbi ng\u01b0\u1eddi d\u00f9ng. Hi v\u1ecdng qua v\u00e0i vi\u1ebft n\u00e0y, b\u1ea1n \u0111\u00e3 gi\u1ea3i \u0111\u00e1p c\u00e1c th\u1eafc m\u1eafc li\u00ean quan \u0111\u1ebfn ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh ph\u1ed5 bi\u1ebfn n\u00e0y.<\/p>\n

Xem th\u00eam:<\/p>\n