{"id":2182,"date":"2017-04-27T16:55:00","date_gmt":"2017-04-27T08:55:00","guid":{"rendered":"http:\/\/www.imzouyang.com\/blog\/?p=2182"},"modified":"2020-10-28T22:46:57","modified_gmt":"2020-10-28T14:46:57","slug":"js%e5%8e%9f%e7%90%86%ef%bc%9a%e5%87%bd%e6%95%b0%e5%8f%82%e6%95%b0%e5%88%b0%e5%ba%95%e6%98%af%e5%80%bc%e4%bc%a0%e9%80%92%e8%bf%98%e6%98%af%e5%bc%95%e7%94%a8%e4%bc%a0%e9%80%92%ef%bc%9f","status":"publish","type":"post","link":"http:\/\/www.imzouyang.com\/blog\/archives\/2182.html","title":{"rendered":"js\u539f\u7406\uff1a\u51fd\u6570\u53c2\u6570\u5230\u5e95\u662f\u503c\u4f20\u9012\u8fd8\u662f\u5f15\u7528\u4f20\u9012\uff1f"},"content":{"rendered":"\n

\u4e00\u3001<\/strong><\/p>\n\n\n\n

\u6709\u7684\u4eba\u8bf4\u662f\u6309\u503c\u4f20\u9012\uff0c\u56e0\u4e3a\uff1a<\/p>\n\n\n\n

var a = 1;\nfunction box(n) {\n    n++;\n    console.log(n);\n}\nbox(a);\/\/2\nconsole.log(a);\/\/1<\/code><\/pre>\n\n\n\n
\u53ef\u4ee5\u770b\u5230\uff0ca \u4e3a\u57fa\u672c\u7c7b\u578b\u503c\u65f6\uff0c\u51fd\u6570\u5185\u90e8\u5bf9\u4f20\u5165\u7684 a \u8fdb\u884c\u4fee\u6539\uff0c\u5e76\u6ca1\u6709\u5f71\u54cd\u5230\u5916\u90e8\u7684 a \u53d8\u91cf\u3002
<\/p>\n\n\n\n
<\/p>\n\n\n\n
\u6709\u7684\u4eba\u8bf4\u662f\u6309\u5f15\u7528\u4f20\u9012\u7684\uff0c\u56e0\u4e3a\uff1a<\/p>\n\n\n\n
var a = {name:\"zou\"};\nfunction box(n) {\n    n.name = \"yang\";\n    console.log(a);\n}\nbox(a);\/\/{name: \"yang\"}\nconsole.log(a);\/\/{name: \"yang\"}<\/code><\/pre>\n\n\n\n
\u53ef\u4ee5\u770b\u5230\uff0ca \u4e3a\u5bf9\u8c61\u65f6\uff0c\u51fd\u6570\u5185\u90e8\u5bf9\u4f20\u5165\u7684 a \u8fdb\u884c\u4fee\u6539\uff0c\u6210\u529f\u5f71\u54cd\u5230\u5916\u90e8\u7684 a \u53d8\u91cf\u3002
<\/p>\n\n\n\n
<\/p>\n\n\n\n
\u53c8\u6709\u4eba\u8bf4\uff0c\u5982\u679c\u5bf9\u8c61\u662f\u6309\u5f15\u7528\u4f20\u5165\u51fd\u6570\u7684\uff0c\u90a3\u4e48\u600e\u4e48\u53c8\u65e0\u6cd5\u5728\u51fd\u6570\u5185\u5bf9\u8be5\u5bf9\u8c61\u91cd\u65b0\u8d4b\u503c\u5462\uff1a<\/p>\n\n\n\n
var a = {name:\"zou\"};\nfunction box(n) {\n    n.name = \"yang\";\n    console.log(a);\n\n    n = {}; \/\/\u5c06 n \u91cd\u65b0\u8d4b\u503c\u4e3a\u7a7a\u5bf9\u8c61\n\n}\nbox(a);\/\/{name: \"yang\"}\nconsole.log(a);\/\/{name: \"yang\"}<\/code><\/pre>\n\n\n\n
\u4e0a\u9762\u51fd\u6570\u5185\u90e8\u5bf9 n \u4fee\u6539\uff0c\u5f71\u54cd\u5230\u4e86\u4f20\u5165\u7684 a \u5bf9\u8c61\uff0c\u5bf9 n \u518d\u91cd\u65b0\u8d4b\u503c\uff0c\u5374\u53c8\u6ca1\u6709\u5f71\u54cd\u5230\u3002
<\/p>\n\n\n\n
\u4e8c\u3001<\/strong><\/p>\n\n\n\n
\u300ajs\u9ad8\u7ea7\u7a0b\u5e8f\u8bbe\u8ba1\u300b\u7ed9\u51fa\u4e86\u7b54\u6848\uff1aECMAScript\u4e2d\u6240\u6709\u51fd\u6570\u7684\u53c2\u6570\u90fd\u662f\u6309\u503c\u4f20\u9012\u7684\u3002<\/p>\n\n\n\n
\u8fd9\u91cc\u7684\u503c\u4f20\u9012\uff0c\u8ddf\u6211\u4eec\u7406\u89e3\u7684\u666e\u901a\u7684\u503c\u7684\u4f20\u9012\u6709\u90a3\u4e48\u70b9\u70b9\u201c\u533a\u522b\u201d\uff0c\u8fd9\u91cc\u7684\u503c\uff0c\u4f20\u9012\u7684\u5176\u5b9e\u662f\u4e00\u4e2a\u8be5\u53c2\u6570\u7684 \u526f\u672c\u62f7\u8d1d\uff0c\u8be5\u526f\u672c\u4f5c\u7528\u57df\u5728\u8be5\u51fd\u6570\u5185\u3002
<\/p>\n\n\n\n
\u5728\u6309\u503c\u8c03\u7528\u4e2d\uff0c\u5bf9\u53c2\u6570\u8868\u8fbe\u5f0f\u8fdb\u884c\u6c42\u503c\uff0c\u5e76\u5c06\u7ed3\u679c\u503c\u7ed1\u5b9a\u5230\u51fd\u6570\u4e2d\u7684\u76f8\u5e94\u53d8\u91cf\uff08\u901a\u5e38\u901a\u8fc7\u5c06\u503c\u590d\u5236\u5230\u65b0\u7684\u5185\u5b58\u533a\u57df\u4e2d\uff09<\/p>
\u5f15\u7528\u81ea\uff1aEvaluation strategy<\/a><\/p><\/blockquote>\n\n\n\n