{"id":4775,"date":"2022-03-27T20:54:06","date_gmt":"2022-03-27T12:54:06","guid":{"rendered":"https:\/\/egonlin.com\/?p=4775"},"modified":"2022-03-27T20:54:06","modified_gmt":"2022-03-27T12:54:06","slug":"%e7%ac%ac%e4%ba%8c%e8%8a%82%ef%bc%9ajs%e7%9a%84%e5%9f%ba%e7%a1%80%e6%95%b0%e6%8d%ae%e7%b1%bb%e5%9e%8b","status":"publish","type":"post","link":"https:\/\/egonlin.com\/?p=4775","title":{"rendered":"\u7b2c\u4e8c\u8282\uff1ajs\u7684\u57fa\u7840\u6570\u636e\u7c7b\u578b"},"content":{"rendered":"

JavaScript\u57fa\u672c\u6570\u636e\u7c7b\u578b<\/h1>\n

1\u3001\u53d8\u91cf\u7684\u5b9a\u4e49<\/h2>\n

JS\u4e2d\u5b9a\u4e49\u53d8\u91cf\uff0c\u4e0d\u540c\u4e8ePython\uff0c\u6211\u4eec\u9700\u8981\u50cfPython\u5b9a\u4e49\u51fd\u6570\u90a3\u6837\uff0c\u4e5f\u9700\u8981\u7528\u7279\u5b9a\u7684\u5173\u952e\u8bcd\u6765\u5b9a\u4e49\u53d8\u91cf\uff1a<\/p>\n

ES5\u8bed\u6cd5\uff0c\u6211\u4eec\u91c7\u7528var\u5173\u952e\u8bcd\u5b9a\u4e49\u53d8\u91cf\uff0c\u5e76\u4e14\u6ca1\u6709\u5e38\u91cf\u7684\u6982\u5ff5<\/p>\n

ES6\u8bed\u6cd5\uff0c\u6211\u4eec\u91c7\u7528let\u5173\u952e\u8bcd\u5b9a\u4e49\u53d8\u91cf\uff0c\u7528const\u5173\u952e\u8bcd\u5b9a\u4e49\u5e38\u91cf<\/p>\n

\u6ce8\uff1a\u6211\u4eec\u4e0d\u9700\u8981\u50cfPython\u90a3\u6837\u5207\u6362\u89e3\u91ca\u5668\u7248\u672c\u6765\u533a\u522b\u5230\u5e95\u8be5\u4e66\u5199\u4ec0\u4e48\u7248\u672c\u8bed\u6cd5\u7684\u4ee3\u7801\uff0c\u5728\u4e00\u4e2aJS\u6587\u4ef6\u4e2d\u6211\u4eec\u53ef\u4ee5\u540c\u65f6\u4e66\u5199\u4e24\u79cd\u8bed\u6cd5\u7684JS\u4ee3\u7801\uff0c\u6d4f\u89c8\u5668\u90fd\u53ef\u4ee5\u81ea\u52a8\u5e2e\u6211\u4eec\u89e3\u6790\u5e76\u8fd0\u884c\u3002<\/p>\n

\/\/ ES5\u5b9a\u4e49\u53d8\u91cf\uff1avar\u662f\u5173\u952e\u8bcd\u3001num\u662f\u53d8\u91cf\u540d\u3001=\u4e3a\u8d4b\u503c\u7b26\u300110\u4e3a\u53d8\u91cf\u503c\u3001;\u4e3aJS\u8bed\u8a00\u8bed\u53e5\u7684\u7ed3\u675f\u6807\u8bc6\u7b26\nvar num = 10;\n\n\/\/ ES6\u5b9a\u4e49\u53d8\u91cf\nlet count = 100;\n\nconst PI = 3.14;<\/code><\/pre>\n
2\u3001\u53d8\u91cf\u7684\u547d\u540d\u89c4\u8303<\/h2>\n
\/*\n1. \u7531\u5b57\u6bcd\uff0c\u6570\u5b57\uff0c_\uff0c$\u7ec4\u6210\uff0c\u4e0d\u80fd\u4ee5\u6570\u5b57\u5f00\u5934\uff08\u53ef\u4ee5\u5305\u542b\u4e2d\u6587\u5b57\u7b26\uff09\n2. \u533a\u5206\u5927\u5c0f\u5199\n3. \u4e0d\u80fd\u51fa\u73b0\u5173\u952e\u5b57\u53ca\u4fdd\u7559\u5b57\n*\/<\/code><\/pre>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
<\/th>\n<\/th>\n<\/th>\n<\/th>\n<\/th>\n<\/tr>\n<\/thead>\n
abstract<\/td>\narguments<\/td>\nboolean<\/td>\nbreak<\/td>\nbyte<\/td>\n<\/tr>\n
case<\/td>\ncatch<\/td>\nchar<\/td>\nclass*<\/td>\nconst<\/td>\n<\/tr>\n
continue<\/td>\ndebugger<\/td>\ndefault<\/td>\ndelete<\/td>\ndo<\/td>\n<\/tr>\n
double<\/td>\nelse<\/td>\nenum*<\/td>\neval<\/td>\nexport*<\/td>\n<\/tr>\n
extends*<\/td>\nfalse<\/td>\nfinal<\/td>\nfinally<\/td>\nfloat<\/td>\n<\/tr>\n
for<\/td>\nfunction<\/td>\ngoto<\/td>\nif<\/td>\nimplements<\/td>\n<\/tr>\n
import*<\/td>\nin<\/td>\ninstanceof<\/td>\nint<\/td>\ninterface<\/td>\n<\/tr>\n
let<\/td>\nlong<\/td>\nnative<\/td>\nnew<\/td>\nnull<\/td>\n<\/tr>\n
package<\/td>\nprivate<\/td>\nprotected<\/td>\npublic<\/td>\nreturn<\/td>\n<\/tr>\n
short<\/td>\nstatic<\/td>\nsuper*<\/td>\nswitch<\/td>\nsynchronized<\/td>\n<\/tr>\n
this<\/td>\nthrow<\/td>\nthrows<\/td>\ntransient<\/td>\ntrue<\/td>\n<\/tr>\n
try<\/td>\ntypeof<\/td>\nvar<\/td>\nvoid<\/td>\nvolatile<\/td>\n<\/tr>\n
while<\/td>\nwith<\/td>\nyield<\/td>\n<\/td>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
3\u3001\u57fa\u672c\u6570\u636e\u7c7b\u578b<\/h2>\n
JS\u8bed\u8a00\u4e2d\u57fa\u672c\u6570\u636e\u7c7b\u578b\u5206\u503c\u7c7b\u578b\u4e0e\u5f15\u7528\u7c7b\u578b\u4e24\u90e8\u5206\u3002<\/p>\n
3-1 \u503c\u7c7b\u578b<\/h3>\n
\/\/ \u6570\u5b57\u7c7b\u578b\uff1anumber\nvar num = 10;\nconst PI = 3.14;\nconsole.log(typeof(num), num);  \/\/ \u7ed3\u679c\uff1anumber  10\n\n\/\/ \u5b57\u7b26\u4e32\u7c7b\u578b\uff1astring\nvar s1 = "\u53cc\u5f15\u53f7\u53ef\u4ee5\u8868\u793a\u5b57\u7b26\u4e32";\nvar s2 = '\u5355\u5f15\u53f7\u53ef\u4ee5\u8868\u793a\u5b57\u7b26\u4e32';\nconsole.log(typeof(s1), s1);  \/\/ \u7ed3\u679c\uff1astring  \u53cc\u5f15\u53f7\u53ef\u4ee5\u8868\u793a\u5b57\u7b26\u4e32\n\n\/\/ \u5e03\u5c14\u7c7b\u578b\uff1aboolean\nvar b1 = true;\nvar b2 = false;\nconsole.log(typeof(b1), b1);  \/\/ \u7ed3\u679c\uff1astring  \u53cc\u5f15\u53f7\u53ef\u4ee5\u8868\u793a\u5b57\u7b26\u4e32\n\n\/\/ \u672a\u5b9a\u4e49\u7c7b\u578b\uff1aundefined\nvar u1;\nvar u2 = undefined;\nconsole.log(typeof(u1), u1);  \/\/ \u7ed3\u679c\uff1aundefined  undefined<\/code><\/pre>\n
3-2 \u5f15\u7528\u7c7b\u578b<\/h3>\n
\/\/ \u51fd\u6570\u7c7b\u578b\uff1afunction\nfunction fn1() {}\nvar fn2 = function() {};\nconsole.log(typeof(fn1), fn1);  \/\/ \u7ed3\u679c\uff1afunction  \u0192 fn1() {}\n\n\/\/ \u5bf9\u8c61\u7c7b\u578b\uff1aobject\nvar obj1 = {}\nconsole.log(typeof(obj1), obj1);  \/\/ \u7ed3\u679c\uff1afunction  {}\n\n\/\/ Array\u5bf9\u8c61\u7c7b\u578b\uff1a\nvar arr1 = [1, 2, 3, 4, 5]\nconsole.log(typeof(arr1), arr1);  \/\/ \u7ed3\u679c\uff1aobject  (5)\u00a0[1, 2, 3, 4, 5]<\/code><\/pre>\n
4\u3001\u8fd0\u7b97\u7b26<\/h2>\n
4-1 \u7b97\u6570\u8fd0\u7b97\u7b26<\/h3>\n
\u524d\u63d0\uff1an = 5<\/p>\n\n\n\n\n\n\n\n\n\n\n\n
\u8fd0\u7b97\u7b26<\/th>\n\u63cf\u8ff0<\/th>\n\u4f8b\u5b50<\/th>\nx\u7ed3\u679c<\/th>\nn\u7ed3\u679c<\/th>\n<\/tr>\n
+<\/td>\n\u52a0\u6cd5<\/td>\nx=n+2<\/td>\n7<\/td>\n5<\/td>\n<\/tr>\n
–<\/td>\n\u51cf\u6cd5<\/td>\nx=n-2<\/td>\n3<\/td>\n5<\/td>\n<\/tr>\n
*<\/td>\n\u4e58\u6cd5<\/td>\nx=n*2<\/td>\n10<\/td>\n5<\/td>\n<\/tr>\n
\/<\/td>\n\u9664\u6cd5<\/td>\nx=n\/2<\/td>\n2.5<\/td>\n5<\/td>\n<\/tr>\n
%<\/td>\n\u53d6\u6a21(\u4f59\u6570)<\/td>\nx=n\/2<\/td>\n1<\/td>\n5<\/td>\n<\/tr>\n
++<\/td>\n\u81ea\u589e<\/td>\nx=++n<\/td>\n6<\/td>\n6<\/td>\n<\/tr>\n
x=n++<\/td>\n5<\/td>\n6<\/td>\n<\/tr>\n
—<\/td>\n\u81ea\u51cf<\/td>\nx=–n<\/td>\n4<\/td>\n4<\/td>\n<\/tr>\n
x=n–<\/td>\n5<\/td>\n4<\/td>\n<\/tr>\n<\/table>\n
4-2 \u8d4b\u503c\u8fd0\u7b97\u7b26<\/h3>\n
\u524d\u63d0\uff1ax=5\uff0cy=5<\/p>\n\n\n\n\n\n\n\n\n\n\n
\u8fd0\u7b97\u7b26<\/th>\n\u4f8b\u5b50<\/th>\n\u7b49\u540c\u4e8e<\/th>\n\u8fd0\u7b97\u7ed3\u679c<\/th>\n<\/tr>\n<\/thead>\n
=<\/td>\nx=y<\/td>\n<\/td>\n5<\/td>\n<\/tr>\n
+=<\/td>\nx+=y<\/td>\nx=x+y<\/td>\n10<\/td>\n<\/tr>\n
-=<\/td>\nx-=y<\/td>\nx=x-y<\/td>\n0<\/td>\n<\/tr>\n
*=<\/td>\nx*=y<\/td>\nx=x*y<\/td>\n25<\/td>\n<\/tr>\n
\/=<\/td>\nx\/=y<\/td>\nx=x\/y<\/td>\n1<\/td>\n<\/tr>\n
%=<\/td>\nx%=y<\/td>\nx=x%y<\/td>\n0<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
4-3 \u6bd4\u8f83\u8fd0\u7b97\u7b26<\/h3>\n
\u524d\u63d0\uff1ax=5<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n
\u8fd0\u7b97\u7b26<\/th>\n\u63cf\u8ff0<\/th>\n\u6bd4\u8f83<\/th>\n\u7ed3\u679c<\/th>\n<\/tr>\n<\/thead>\n
==<\/td>\n\u7b49\u4e8e<\/td>\nx=="5"<\/td>\ntrue<\/td>\n<\/tr>\n
===<\/td>\n\u7edd\u5bf9\u7b49\u4e8e<\/td>\nx==="5"<\/td>\nfalse<\/td>\n<\/tr>\n
!=<\/td>\n\u4e0d\u7b49\u4e8e<\/td>\nx!="5"<\/td>\nfales<\/td>\n<\/tr>\n
!==<\/td>\n\u4e0d\u7edd\u5bf9\u7b49\u4e8e<\/td>\nx!=="5"<\/td>\ntrue<\/td>\n<\/tr>\n
><\/td>\n\u5927\u4e8e<\/td>\nx>5<\/td>\nfalse<\/td>\n<\/tr>\n
<<\/td>\n\u5c0f\u4e8e<\/td>\nx<5<\/td>\nfalse<\/td>\n<\/tr>\n
>=<\/td>\n\u5927\u4e8e\u7b49\u4e8e<\/td>\nx>=5<\/td>\ntrue<\/td>\n<\/tr>\n
<=<\/td>\n\u5c0f\u4e8e\u7b49\u4e8e<\/td>\nx<=5<\/td>\ntrue<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
4-4 \u903b\u8f91\u8fd0\u7b97\u7b26<\/h3>\n
\u524d\u63d0\uff1an=5<\/p>\n\n\n\n\n\n\n\n
\u8fd0\u7b97\u7b26<\/th>\n\u63cf\u8ff0<\/th>\n\u4f8b\u5b50<\/th>\n\u7ed3\u679c<\/th>\n<\/tr>\n<\/thead>\n
&&<\/td>\n\u4e0e<\/td>\nx=n>10&&++n<\/td>\nx=false,n=5\uff08\u77ed\u8def\uff09<\/td>\n<\/tr>\n
||<\/td>\n\u6216<\/td>\nx=n<10||n–<\/td>\nx=true,n=5\uff08\u77ed\u8def\uff09<\/td>\n<\/tr>\n
!<\/td>\n\u975e<\/td>\nx=!n<\/td>\nx=false,x=5<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
4-5 \u4e09\u76ee\u8fd0\u7b97\u7b26<\/h3>\n
\/\/ \u7ed3\u679c = \u6761\u4ef6\u8868\u8fbe\u5f0f ? \u7ed3\u679c1 : \u7ed3\u679c2;\n\/\/ \u8bed\u6cd5\u89c4\u5219\uff1a\u6761\u4ef6\u8868\u8fbe\u5f0f\u6210\u7acb\uff0c\u5c06\u7ed3\u679c1\u8d4b\u503c\u7ed9\u7ed3\u679c\uff0c\u53cd\u6b63\u8d4b\u503c\u7ed3\u679c2\n\n\/\/ \u6848\u4f8b\uff1a\nvar weather = prompt("\u5929\u6c14(\u6674|\u96e8)");  \/\/ \u6587\u672c\u8f93\u5165\u5f39\u51fa\u6846\nvar res = tq == '\u6674' ? "\u4eca\u5929\u5929\u6c14\u633a\u597d" : "\u8bf7\u5047\u56de\u5bb6\u6536\u8863\u670d";\nconsole.log(res);  \/\/ \u4eca\u5929\u5929\u6c14\u633a\u597d<\/code><\/pre>\n
<\/h4>\n","protected":false},"excerpt":{"rendered":"
JavaScript\u57fa\u672c\u6570\u636e\u7c7b\u578b 1\u3001\u53d8\u91cf\u7684\u5b9a\u4e49 JS\u4e2d\u5b9a\u4e49\u53d8\u91cf\uff0c\u4e0d\u540c\u4e8ePython\uff0c\u6211\u4eec\u9700\u8981\u50cfPython\u5b9a […]<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[361,366],"tags":[],"_links":{"self":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/posts\/4775"}],"collection":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=4775"}],"version-history":[{"count":0,"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/posts\/4775\/revisions"}],"wp:attachment":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=4775"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=4775"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=4775"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}