Ghi ch\u00fa: T\u00e0i li\u1ec7u tr\u00edch d\u1eabn<\/p>\n\n\n\n
L\u1eadp tr\u00ecnh<\/a> \u0111\u1ed1i t\u01b0\u1ee3ng l\u00e0 m\u1ed9t trong nh\u1eefng thu\u1eadt ng\u1eef \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng nhi\u1ec1u trong l\u0129nh v\u1ef1c c\u00f4ng ngh\u1ec7 th\u00f4ng tin. V\u1eady oop l\u00e0 g\u00ec? h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng l\u00e0 g\u00ec? T\u1ea5t c\u1ea3 nh\u1eefng c\u00e2u h\u1ecfi n\u00e0y s\u1ebd \u0111\u01b0\u1ee3c ch\u00fang t\u00f4i gi\u1ea3i \u0111\u00e1p trong n\u1ed9i dung b\u00e0i vi\u1ebft d\u01b0\u1edbi \u0111\u00e2y.<\/p>\n\n\n\n OOP l\u00e0 g\u00ec? Kh\u00e1i ni\u1ec7m li\u00ean quan<\/p>\n\n\n\n Kh\u00e1i ni\u1ec7m l\u1eadp tr\u00ecnh<\/a> h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng l\u00e0 g\u00ec?<\/p>\n\n\n\n L\u1eadp tr\u00ecnh<\/a> h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng c\u00f3 t\u00ean ti\u1ebfng anh l\u00e0 Object Oriented Programming v\u00e0 vi\u1ebft t\u1eaft l\u00e0 OOP. \u0110\u00e2y l\u00e0 m\u1ed9t trong nh\u1eefng k\u1ef9 thu\u1eadt l\u1eadp tr\u00ecnh<\/a> cho ph\u00e9p l\u1eadp tr\u00ecnh<\/a> vi\u00ean t\u1ea1o ra c\u00e1c \u0111\u1ed1i t\u01b0\u1ee3ng trong code tr\u1eebu t\u01b0\u1ee3ng h\u00f3a v\u00e0 c\u00e1c \u0111\u1ed1i t\u01b0\u1ee3ng th\u1ef1c t\u1ebf trong cu\u1ed9c s\u1ed1ng.<\/p>\n\n\n\n Theo \u0111\u1ecbnh ngh\u0129a tr\u00ean wikipedia, l\u1eadp tr\u00ecnh<\/a> \u0111\u1ed1i t\u01b0\u1ee3ng l\u00e0 m\u1ed9t m\u1eabu l\u1eadp tr\u00ecnh<\/a> d\u1ef1a tr\u00ean kh\u00e1i ni\u1ec7m c\u00f4ng ngh\u1ec7 \u0111\u1ed1i t\u01b0\u1ee3ng. M\u00e0 \u1edf \u0111\u00f3, \u0111\u1ed1i t\u01b0\u1ee3ng ch\u1ee9a \u0111\u1ef1ng c\u00e1c d\u1eef li\u1ec7u, tr\u00ean c\u00e1c tr\u01b0\u1eddng th\u01b0\u1eddng \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 c\u00e1c thu\u1ed9c t\u00ednh; v\u00e0 m\u00e3 ngu\u1ed3n \u0111\u01b0\u1ee3c t\u1ed5 ch\u1ee9c th\u00e0nh c\u00e1c ph\u01b0\u01a1ng th\u1ee9c. Ph\u01b0\u01a1ng th\u1ee9c gi\u00fap cho c\u00e1c \u0111\u1ed1i t\u01b0\u1ee3ng c\u00f3 th\u1ec3 truy xu\u1ea5t v\u00e0 hi\u1ec7u ch\u1ec9nh c\u00e1c tr\u01b0\u1eddng duex li\u1ec7u c\u1ee7a \u0111\u1ed1i t\u01b0\u1ee3ng kh\u00e1c.<\/p>\n\n\n\n Hi\u1ec3u m\u1ed9t c\u00e1ch \u0111\u01a1n gi\u1ea3n, l\u1eadp tr\u00ecnh \u0111\u1ed1i t\u01b0\u1ee3ng l\u00e0 ph\u01b0\u01a1ng ph\u00e1p l\u1eadp tr\u00ecnh l\u1ea5y \u0111\u1ed1i t\u01b0\u1ee3ng l\u00e0m n\u1ec1n t\u1ea3ng \u0111\u1ec3 x\u00e2y d\u1ef1ng ch\u01b0\u01a1ng tr\u00ecnh. Ho\u1eb7c \u0111\u00e2y l\u00e0 ph\u01b0\u01a1ng ph\u00e1p l\u1eadp tr\u00ecnh d\u1ef1 r\u00ean ki\u1ebfn tr\u00fac l\u1edbp v\u00e0 \u0111\u1ed1i t\u01b0\u1ee3ng.<\/p>\n\n\n\n Object l\u00e0 g\u00ec?<\/p>\n\n\n\n \u0110\u1ed1i t\u01b0\u1ee3ng Object c\u00f3 th\u1ec3 l\u00e0 \u0111i\u1ec7n tho\u1ea1i, con ng\u01b0\u1eddi, m\u00e1y t\u00ednh,\u2026v\u00e0 \u0111i\u1ec3m chung l\u00e0 \u0111\u1ec1u g\u1ed3m c\u00f3 2 th\u00e0nh ph\u1ea7n ch\u00ednh \u0111\u00f3 l\u00e0:<\/p>\n\n\n\n Thu\u1ed9c t\u00ednh (Attribute): l\u00e0 nh\u1eefng th\u00f4ng tin, \u0111\u1eb7c \u0111i\u1ec3m c\u1ee7a \u0111\u1ed1i t\u01b0\u1ee3ng<\/p>\n\n\n\n Ph\u01b0\u01a1ng th\u1ee9c (Method): l\u00e0 nh\u1eefng h\u00e0nh \u0111\u1ed9ng m\u00e0 \u0111\u1ed1i t\u01b0\u1ee3ng c\u00f3 th\u1ec3 th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c.<\/p>\n\n\n\n C\u00e1c \u0111\u1eb7c \u0111i\u1ec3m c\u1ee7a l\u1eadp tr\u00ecnh \u0111\u1ed1i t\u01b0\u1ee3ng<\/p>\n\n\n\n T\u00ednh \u0111\u00f3ng g\u00f3i ( Encapsulation)<\/p>\n\n\n\n T\u00ednh ch\u1ea5t n\u00e0y s\u1ebd kh\u00f4ng cho ph\u00e9p ng\u01b0\u1eddi d\u00f9ng tr\u1ef1c ti\u1ebfp t\u00e1c \u0111\u1ed9ng \u0111\u1ebfn d\u1eef li\u1ec7u b\u00ean trong c\u1ee7a \u0111\u1ed1i t\u01b0\u1ee3ng m\u00e0 ph\u1ea3i th\u00f4ng qua c\u00e1c ph\u01b0\u01a1ng th\u1ee9c m\u00e0 \u0111\u1ed1i t\u01b0\u1ee3ng cung c\u1ea5p. T\u00ednh ch\u1ea5t n\u00e0y \u0111\u1ea3m b\u1ea3o t\u00ednh v\u1eb9n to\u00e0n c\u1ee7a \u0111\u1ed1i t\u01b0\u1ee3ng.<\/p>\n\n\n\n Trong \u0111o\u1ea1n code tr\u00ean, t\u00ednh \u0111\u00f3ng g\u00f3i \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n qua thu\u1ed9c t\u00ednh mausac, chieudai, chieurong v\u00e0 c\u00e1c ph\u01b0\u01a1ng th\u1ee9c input, output. B\u1ea1n s\u1ebd kh\u00f4ng th\u1ec3 truy c\u1eadp \u0111\u1ebfn c\u00e1c private data ho\u1eb7c g\u1ecdi \u0111\u1ebfn private methods c\u1ee7a class t\u1eeb b\u00ean ngo\u00e0i.<\/p>\n\n\n\n T\u00ednh k\u1ebf th\u1eeba (Inheritance)<\/p>\n\n\n\n K\u1ebf th\u1eeba, t\u00e1i s\u1eed d\u1ee5ng thu\u1ed9c t\u00ednh, ph\u01b0\u01a1ng th\u1ee9c c\u1ee7a l\u1edbp c\u01a1 s\u1edf v\u00e0 l\u1edbp k\u1ebf th\u1eeba \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 l\u1edbp con. L\u1edbp con n\u00e0y s\u1ebd th\u1eeba h\u01b0\u1edfng nh\u1eefng g\u00ec l\u1edbp cha c\u00f3 v\u00e0 cho ph\u00e9p.<\/p>\n\n\n\n T\u00ednh tr\u1eebu t\u01b0\u1ee3ng ( Abstraction)<\/p>\n\n\n\n T\u1eadp trung v\u00e0o c\u1ed1t l\u00f5i c\u1ee7a \u0111\u1ed1i t\u01b0\u1ee3ng, b\u1ecf qua nh\u1eefng th\u1ee9 kh\u00f4ng quan tr\u1ecdng v\u00e0 kh\u00f4ng li\u00ean quan.<\/p>\n\n\n\n T\u00ednh \u0111a h\u00ecnh ( Polymorphism)<\/p>\n\n\n\n T\u00ednh \u0111a h\u00ecnh cho ph\u00e9p c\u00e1c ch\u1ee9c n\u0103ng (method) kh\u00e1c nhau \u0111\u01b0\u1ee3c th\u1ef1c thi tr\u00ean c\u00e1c \u0111\u1ed1i t\u01b0\u1ee3ng kh\u00e1c nhau.<\/p>\n\n\n\n => Tr\u1eebu t\u01b0\u1ee3ng, k\u1ebf th\u1eeba, \u0111a h\u00ecnh v\u00e0 \u0111\u00f3ng g\u00f3i 4 t\u00ednh ch\u1ea5t oop m\u00e0 nh\u1eefng ai \u0111ang h\u1ecdc v\u00e0 l\u00e0m l\u1eadp tr\u00ecnh ph\u1ea3i n\u1eafm ch\u1eafc b\u1edfi ch\u00fang s\u1ebd lu\u00f4n \u0111i k\u00e8m v\u1edbi c\u00e1c k\u1ef9 thu\u1eadt kh\u00e1c trong l\u1eadp tr\u00ecnh.<\/p>\n\n\n\n C\u00e1c t\u00ednh ch\u1ea5t l\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng PHP<\/p>\n\n\n\n H\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng PHP c\u0169ng c\u00f3 4 \u0111\u1eb7c \u0111i\u1ec3m c\u01a1 b\u1ea3n \u0111\u00f3 l\u00e0:<\/p>\n\n\n\n T\u00ednh \u0111\u00f3ng g\u00f3i<\/p>\n\n\n\n Trong PHP vi\u1ec7c \u0111\u00f3ng g\u00f3i \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n nh\u1edd s\u1eed d\u1ee5ng c\u00e1c t\u1eeb kh\u00f3a public, private v\u00e0 protected:<\/p>\n\n\n\n public: Cho ph\u00e9p truy c\u1eadp v\u00e0 l\u00e0m thay \u0111\u1ed5i gi\u00e1 tr\u1ecb thu\u1ed9c t\u00ednh v\u00e0 ph\u01b0\u01a1ng tr\u00ecnh \u1edf m\u1ecdi h\u00e0nh vi. C\u00f3 th\u1ec3 hi\u1ec3u l\u00e0 mang t\u00ednh c\u1ed9ng \u0111\u1ed3ng.<\/p>\n\n\n\n private: Cho ph\u00e9p truy c\u1eadp ho\u1eb7c thay \u0111\u1ed5i gi\u00e1 tr\u1ecb c\u1ee7a thu\u1ed9c t\u00ednh v\u00e0 ph\u01b0\u01a1ng th\u1ee9c \u1edf ph\u1ea1m vi c\u1ee7a \u0111\u1ed1i t\u01b0\u1ee3ng. C\u00f3 th\u1ec3 hi\u1ec3u l\u00e0 mang t\u00ednh gia \u0111\u00ecnh.<\/p>\n\n\n\n protected: Ch\u1ec9 cho ph\u00e9p truy c\u1eadp ho\u1eb7c thay \u0111\u1ed5i gi\u00e1 tr\u1ecb c\u1ee7a thu\u1ed9c t\u00ednh v\u00e0 ph\u01b0\u01a1ng th\u1ee9c \u1edf ph\u1ea1m v\u1ecb c\u1ee7a c\u00e1c \u0111\u1ed1i t\u01b0\u1ee3ng con. Mang t\u00ednh d\u00f2ng h\u1ecd.<\/p>\n\n\n\n T\u00ednh k\u1ebf th\u1eeba<\/p>\n\n\n\n M\u1ed9t l\u1edbp c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c k\u1ebf th\u1eeba t\u1eeb m\u1ed9t l\u1edbp kh\u00e1c. Vi\u1ec7c k\u1ebf th\u1eeba \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n th\u00f4ng qua vi\u1ec7c s\u1eed d\u1ee5ng t\u1eeb kh\u00f3a extends. \u0110\u1ed1i t\u01b0\u1ee3ng thu\u1ed9c l\u1edbp con s\u1ebd c\u00f3 thu\u1ed9c t\u00ednh v\u00e0 ph\u01b0\u01a1ng th\u1ee9c protected v\u00e0 public c\u1ee7a l\u1edbp m\u00e0 n\u00f3 k\u1ebf th\u1eeba.<\/p>\n\n\n\n T\u00ednh tr\u1eebu t\u01b0\u1ee3ng<\/p>\n\n\n\n PHP c\u00f3 abstract class v\u00e0 interface \u0111\u1ec3 tr\u1eebu t\u01b0\u1ee3ng c\u00e1c \u0111\u1ed1i t\u01b0\u1ee3ng. V\u00ed d\u1ee5 nh\u01b0 khi b\u1ea1n t\u1ea1o ra m\u1ed9t l\u1edbp (class) d\u00f9ng \u0111\u1ea1i di\u1ec7n cho c\u00e1c t\u00e0i kho\u1ea3n g\u1eedi ti\u1ec1n ng\u00e2n h\u00e0ng c\u1ee7a c\u00e1c kh\u00e1ch h\u00e0ng v\u00e0 \u0111\u1eb7t t\u00ean cho l\u1edbp n\u00e0y l\u00e0 BankAccount. L\u1edbp n\u00e0y c\u00f3 2 thu\u1ed9c t\u00ednh \u0111\u00f3 l\u00e0 $balance v\u00e0 $interest d\u00f9ng \u0111\u1ec3 l\u01b0u d\u1eef li\u1ec7u s\u1ed1 ti\u1ec1n v\u00e0 l\u00e3i su\u1ea5t ti\u1ec1n g\u1eedi c\u1ee7a t\u00e0i kho\u1ea3n.<\/p>\n\n\n\n T\u00ednh \u0111a h\u00ecnh<\/p>\n\n\n\n OOP PHP trong php t\u00ednh \u0111a h\u00ecnh th\u00ec:<\/p>\n\n\n\n C\u00e1c l\u1edbp con c\u00f3 th\u1ec3 m\u1edf r\u1ed9ng ho\u1eb7c vi\u1ebft l\u1ea1i ph\u01b0\u01a1ng th\u1ee9c c\u1ee7a l\u1edbp cha m\u00e0 n\u00f3 k\u1ebf th\u1eeba.<\/p>\n\n\n\n C\u00e1c class v\u00e0 implement m\u1ed9t interface nh\u01b0ng ch\u00fang c\u00f3 c\u00e1ch th\u1ee9c th\u1ef1c hi\u1ec7n kh\u00e1c nhau cho c\u00e1c method c\u1ee7a interface \u0111\u00f3. C\u00f9ng m\u1ed9t ph\u01b0\u01a1ng th\u1ee9c nh\u01b0ng s\u1ebd cho ra c\u00e1c k\u1ebft qu\u1ea3 kh\u00e1c nhau \u0111\u01b0\u1ee3c g\u1ecdi b\u1edfi c\u00e1c \u0111\u1ed1i t\u01b0\u1ee3ng thu\u1ed9c l\u1edbp kh\u00e1c nhau.<\/p>\n\n\n\n L\u1eadp tr\u00ecnh h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng C++<\/p>\n\n\n\n C++ l\u00e0 ng\u00f4n ng\u1eef l\u1eadp tr\u00ecnh \u0111\u1ed1i t\u01b0\u1ee3ng kh\u00e1 ph\u1ed5 bi\u1ebfn v\u00e0 th\u01b0\u1eddng \u0111\u01b0\u1ee3c gi\u1edbi thi\u1ec7u \u0111\u1ebfn c\u00e1c b\u1ea1n sinh vi\u00ean khi b\u1eaft \u0111\u1ea7u l\u00e0m quen v\u1edbi ph\u01b0\u01a1ng ph\u00e1p l\u1eadp tr\u00ecnh \u0111\u1ed1i t\u01b0\u1ee3ng. C++ oop \u0111\u01b0\u1ee3c x\u1ebfp v\u00e0o nh\u00f3m l\u1eadp tr\u00ecnh b\u1eadc th\u1ea5p, c\u00f3 kh\u1ea3 n\u0103ng x\u1eed l\u00fd nhanh do s\u1ef1 can thi\u1ec7p c\u1ea5p h\u1ec7 th\u1ed1ng. \u0110i\u1ec1u n\u00e0y gi\u00fap cho h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng C++ l\u00e0 s\u1ef1 l\u1ef1a ch\u1ecdn s\u1ed1 1 cho c\u00e1c \u1ee9ng d\u1ee5ng t\u1ed1c \u0111\u1ed9 nh\u01b0 ph\u1ea7n m\u1ec1m nh\u00fang, ph\u1ea7n m\u1ec1m h\u1ec7 th\u1ed1ng,\u2026.<\/p>\n\n\n\n V\u1edbi c\u00e1c th\u00f4ng tin tr\u00ean \u0111\u00e2y, hy v\u1ecdng s\u1ebd gi\u00fap b\u1ea1n tr\u1ea3 l\u1eddi \u0111\u01b0\u1ee3c c\u00e2u h\u1ecfi oop l\u00e0 g\u00ec r\u1ed3i ch\u1ee9. B\u1ea5t k\u1ef3 th\u1eafc m\u1eafc, \u00fd ki\u1ebfn \u0111\u00f3ng g\u00f3p n\u00e0o qu\u00fd kh\u00e1ch h\u00e0ng h\u00e3y comment ph\u00ed d\u01b0\u1edbi, nh\u00e2n vi\u00ean t\u01b0 v\u1ea5n c\u1ee7a Vietlearn.org s\u1eb5n s\u00e0ng t\u01b0 v\u1ea5n, gi\u1ea3i \u0111\u00e1p b\u1ea1n m\u1ecdi l\u00fac, m\u1ecdi n\u01a1i.<\/p>\n\n\n\n <\/p>\n\n\n\n\n\n\n","protected":false},"excerpt":{"rendered":" Ghi ch\u00fa: T\u00e0i li\u1ec7u tr\u00edch d\u1eabn L\u1eadp tr\u00ecnh \u0111\u1ed1i t\u01b0\u1ee3ng l\u00e0 m\u1ed9t trong nh\u1eefng thu\u1eadt ng\u1eef \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng nhi\u1ec1u trong l\u0129nh v\u1ef1c c\u00f4ng ngh\u1ec7 th\u00f4ng tin. V\u1eady oop l\u00e0 g\u00ec? h\u01b0\u1edbng \u0111\u1ed1i t\u01b0\u1ee3ng l\u00e0 g\u00ec? T\u1ea5t c\u1ea3 nh\u1eefng c\u00e2u h\u1ecfi n\u00e0y s\u1ebd \u0111\u01b0\u1ee3c ch\u00fang t\u00f4i gi\u1ea3i \u0111\u00e1p trong n\u1ed9i dung b\u00e0i vi\u1ebft d\u01b0\u1edbi \u0111\u00e2y. […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_disable_autopaging":false},"categories":[13],"tags":[],"class_list":["post-3400","post","type-post","status-publish","format-standard","hentry","category-tin-hoc"],"_links":{"self":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/3400","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/comments?post=3400"}],"version-history":[{"count":0,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/3400\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/media?parent=3400"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/categories?post=3400"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/tags?post=3400"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}