{"id":3164,"date":"2025-03-25T23:42:23","date_gmt":"2025-03-25T15:42:23","guid":{"rendered":"https:\/\/www.laixuexila.com\/?p=3164"},"modified":"2025-03-25T23:42:23","modified_gmt":"2025-03-25T15:42:23","slug":"go-%e8%af%ad%e8%a8%80%e5%b8%b8%e9%87%8f%ef%bc%88constant%ef%bc%89%e8%af%a6%e8%a7%a3","status":"publish","type":"post","link":"https:\/\/www.laixuexila.com\/index.php\/2025\/03\/25\/go-%e8%af%ad%e8%a8%80%e5%b8%b8%e9%87%8f%ef%bc%88constant%ef%bc%89%e8%af%a6%e8%a7%a3\/","title":{"rendered":"Go \u8bed\u8a00\u5e38\u91cf\uff08Constant\uff09\u8be6\u89e3"},"content":{"rendered":"\n

\u5728 Go \u8bed\u8a00\u4e2d\uff0c\u5e38\u91cf\uff08Constant\uff09<\/strong> \u662f\u6307\u503c\u5728\u7a0b\u5e8f\u8fd0\u884c\u671f\u95f4\u4e0d\u4f1a\u53d1\u751f\u53d8\u5316\u7684\u53d8\u91cf<\/strong>\u3002Go \u8bed\u8a00\u4f7f\u7528 const<\/code> \u5173\u952e\u5b57\u6765\u5b9a\u4e49\u5e38\u91cf\u3002<\/p>\n\n\n\n

\n\n\n\n

1. Go \u8bed\u8a00\u5e38\u91cf\u7684\u7279\u70b9<\/strong><\/h2>\n\n\n\n
    \n
  • \u5fc5\u987b\u5728\u7f16\u8bd1\u65f6\u786e\u5b9a\u503c<\/strong>\uff0c\u4e0d\u80fd\u7531\u8fd0\u884c\u65f6\u8ba1\u7b97\u5f97\u51fa\uff08\u4f8b\u5982\uff0c\u51fd\u6570\u8fd4\u56de\u503c\u4e0d\u80fd\u7528\u4e8e\u5e38\u91cf\u8d4b\u503c\uff09\u3002<\/li>\n\n\n\n
  • \u53ea\u80fd\u662f\u57fa\u672c\u6570\u636e\u7c7b\u578b<\/strong>\uff08bool<\/code>\u3001string<\/code>\u3001int<\/code>\u3001float<\/code>\u3001complex<\/code> \u7b49\uff09\u3002<\/li>\n\n\n\n
  • \u4e0d\u80fd\u4f7f\u7528 :=<\/code> \u8bed\u6cd5<\/strong>\uff08Go \u8bed\u8a00\u4e2d :=<\/code> \u53ea\u80fd\u7528\u4e8e\u53d8\u91cf\uff09\u3002<\/li>\n<\/ul>\n\n\n\n
    \n\n\n\n

    2. \u5e38\u91cf\u7684\u58f0\u660e<\/strong><\/h2>\n\n\n\n

    \uff081\uff09\u57fa\u672c\u8bed\u6cd5<\/strong><\/h3>\n\n\n\n
    const \u5e38\u91cf\u540d = \u503c<\/code><\/pre>\n\n\n\n
    \u793a\u4f8b\uff1a<\/p>\n\n\n\n
    package main\n\nimport \"fmt\"\n\nfunc main() {\n    const pi = 3.14159\n    const message = \"Hello, Go!\"\n\n    fmt.Println(pi)       \/\/ \u8f93\u51fa 3.14159\n    fmt.Println(message)  \/\/ \u8f93\u51fa Hello, Go!\n}<\/code><\/pre>\n\n\n\n
    \uff082\uff09\u663e\u5f0f\u7c7b\u578b\u5e38\u91cf<\/strong><\/h3>\n\n\n\n
    const a int = 100\nconst b float64 = 3.14\nconst c string = \"GoLang\"<\/code><\/pre>\n\n\n\n
    \uff083\uff09\u9690\u5f0f\u7c7b\u578b\u5e38\u91cf<\/strong><\/h3>\n\n\n\n
    const x = 42\nconst y = \"Hello\"<\/code><\/pre>\n\n\n\n
    \u5728\u8fd9\u79cd\u60c5\u51b5\u4e0b\uff0cGo \u81ea\u52a8\u63a8\u5bfc\u5e38\u91cf\u7c7b\u578b<\/strong>\u3002<\/p>\n\n\n\n
    \n\n\n\n
    3. \u591a\u4e2a\u5e38\u91cf\u7684\u58f0\u660e<\/strong><\/h2>\n\n\n\n
    \uff081\uff09\u5355\u884c\u58f0\u660e\u591a\u4e2a\u5e38\u91cf<\/strong><\/h3>\n\n\n\n
    const a, b, c = 1, \"Go\", 3.14\nfmt.Println(a, b, c) \/\/ \u8f93\u51fa 1 Go 3.14<\/code><\/pre>\n\n\n\n
    \uff082\uff09\u591a\u884c\u5206\u7ec4\u58f0\u660e<\/strong><\/h3>\n\n\n\n
    const (\n    name  = \"Alice\"\n    age   = 25\n    score = 99.5\n)<\/code><\/pre>\n\n\n\n
    \u8fd9\u79cd\u65b9\u5f0f\u63d0\u9ad8\u4e86\u53ef\u8bfb\u6027\uff0c\u63a8\u8350\u4f7f\u7528<\/strong>\u3002<\/p>\n\n\n\n
    \n\n\n\n
    4. \u5e38\u91cf\u7684\u8ba1\u7b97<\/strong><\/h2>\n\n\n\n
    \u5e38\u91cf\u53ef\u4ee5\u7528\u4e8e\u7f16\u8bd1\u671f\u8ba1\u7b97<\/strong>\uff1a<\/p>\n\n\n\n
    const (\n    a = 10\n    b = 20\n    c = a + b \/\/ 30\n)\nfmt.Println(c)<\/code><\/pre>\n\n\n\n
    \u4f46\u662f\uff0c\u5e38\u91cf\u4e0d\u80fd\u7531\u8fd0\u884c\u65f6\u8ba1\u7b97\u5f97\u51fa<\/strong>\uff1a<\/p>\n\n\n\n
    func getValue() int {\n    return 100\n}\n\nconst x = getValue()  \/\/ \u274c \u62a5\u9519\uff0c\u51fd\u6570\u8fd4\u56de\u503c\u4e0d\u80fd\u7528\u4e8e\u5e38\u91cf<\/code><\/pre>\n\n\n\n
    \n\n\n\n
    5. iota \u5e38\u91cf\u751f\u6210\u5668<\/strong><\/h2>\n\n\n\n
    iota<\/code> \u662f Go \u8bed\u8a00\u7684\u5e38\u91cf\u8ba1\u6570\u5668<\/strong>\uff0c\u9ed8\u8ba4\u4ece 0<\/code> \u5f00\u59cb\uff0c\u6bcf\u5b9a\u4e49\u4e00\u4e2a\u5e38\u91cf iota<\/code> \u9012\u589e 1<\/code><\/strong>\u3002<\/p>\n\n\n\n
    \uff081\uff09\u57fa\u7840\u7528\u6cd5<\/strong><\/h3>\n\n\n\n
    const (\n    a = iota  \/\/ 0\n    b = iota  \/\/ 1\n    c = iota  \/\/ 2\n)\nfmt.Println(a, b, c) \/\/ \u8f93\u51fa 0 1 2<\/code><\/pre>\n\n\n\n
    \uff082\uff09\u7b80\u5199\u65b9\u5f0f<\/strong><\/h3>\n\n\n\n
    const (\n    a = iota  \/\/ 0\n    b         \/\/ 1\n    c         \/\/ 2\n)\nfmt.Println(a, b, c) \/\/ \u8f93\u51fa 0 1 2<\/code><\/pre>\n\n\n\n
    \u7701\u7565 iota<\/code>\uff0cGo \u8bed\u8a00\u4f1a\u81ea\u52a8\u63a8\u5bfc\u3002<\/strong><\/p>\n\n\n\n
    \uff083\uff09iota \u7ed3\u5408\u4f4d\u8fd0\u7b97<\/strong><\/h3>\n\n\n\n
    const (\n    a = 1 << iota  \/\/ 1  (2^0)\n    b              \/\/ 2  (2^1)\n    c              \/\/ 4  (2^2)\n    d              \/\/ 8  (2^3)\n)\nfmt.Println(a, b, c, d) \/\/ \u8f93\u51fa 1 2 4 8<\/code><\/pre>\n\n\n\n
    \u5e38\u89c1\u7528\u4e8e\u5b9a\u4e49<\/strong> \u4e8c\u8fdb\u5236\u6807\u5fd7\u4f4d\uff08Bit Flags\uff09<\/strong>\u3002<\/p>\n\n\n\n
    \uff084\uff09iota \u9047\u5230\u4e2d\u65ad<\/strong><\/h3>\n\n\n\n
    \u5982\u679c\u67d0\u884c\u6709\u503c\uff0ciota<\/code> \u4ecd\u4f1a\u9012\u589e\uff1a<\/p>\n\n\n\n
    const (\n    a = iota  \/\/ 0\n    b = 100   \/\/ 100\uff08\u624b\u52a8\u8d4b\u503c\uff09\n    c = iota  \/\/ 2\uff08\u6062\u590d\u8ba1\u6570\uff09\n    d         \/\/ 3\uff08\u7ee7\u7eed\u8ba1\u6570\uff09\n)\nfmt.Println(a, b, c, d) \/\/ \u8f93\u51fa 0 100 2 3<\/code><\/pre>\n\n\n\n
    \uff085\uff09iota \u5b9e\u73b0\u679a\u4e3e<\/strong><\/h3>\n\n\n\n
    type Weekday int\n\nconst (\n    Sunday Weekday = iota\n    Monday\n    Tuesday\n    Wednesday\n    Thursday\n    Friday\n    Saturday\n)\nfmt.Println(Sunday, Monday, Saturday) \/\/ \u8f93\u51fa 0 1 6<\/code><\/pre>\n\n\n\n
    \u9002\u7528\u4e8e\u5b9a\u4e49\u679a\u4e3e\u7c7b\u578b\u3002<\/strong><\/p>\n\n\n\n
    \n\n\n\n
    6. \u5e38\u91cf\u4e0e var<\/code> \u7684\u533a\u522b<\/strong><\/h2>\n\n\n\n
    \u7279\u6027<\/strong><\/th>\u5e38\u91cf\uff08const\uff09<\/strong><\/th>\u53d8\u91cf\uff08var\uff09<\/strong><\/th><\/tr><\/thead>
    \u662f\u5426\u53ef\u4fee\u6539<\/td>\u274c \u4e0d\u53ef\u4fee\u6539<\/td>\u2705 \u53ef\u4fee\u6539<\/td><\/tr>
    \u662f\u5426\u5fc5\u987b\u521d\u59cb\u5316<\/td>\u2705 \u5fc5\u987b\u521d\u59cb\u5316<\/td>\u274c \u53ef\u4ee5\u4e0d\u521d\u59cb\u5316<\/td><\/tr>
    \u8fd0\u884c\u65f6\u8ba1\u7b97<\/td>\u274c \u4e0d\u652f\u6301<\/td>\u2705 \u652f\u6301<\/td><\/tr>
    \u4f5c\u7528\u57df<\/td>\u6574\u4e2a\u5305<\/strong>\uff08\u5c40\u90e8\/\u5168\u5c40\uff09<\/td>\u6574\u4e2a\u5305<\/strong>\uff08\u5c40\u90e8\/\u5168\u5c40\uff09<\/td><\/tr>
    :=<\/code> \u8d4b\u503c<\/td>\u274c \u4e0d\u652f\u6301<\/td>\u2705 \u652f\u6301<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
    \n\n\n\n
    7. \u603b\u7ed3<\/strong><\/h2>\n\n\n\n
    \u5173\u952e\u70b9<\/strong><\/th>\u8bf4\u660e<\/strong><\/th><\/tr><\/thead>
    \u5e38\u91cf\u5b9a\u4e49<\/strong><\/td>\u4f7f\u7528 const<\/code> \u5173\u952e\u5b57<\/td><\/tr>
    \u7c7b\u578b<\/strong><\/td>\u652f\u6301 int<\/code>\u3001float<\/code>\u3001string<\/code>\u3001bool<\/code><\/td><\/tr>
    \u4e0d\u53ef\u53d8\u6027<\/strong><\/td>\u5e38\u91cf\u503c\u4e00\u65e6\u5b9a\u4e49\uff0c\u4e0d\u80fd\u4fee\u6539<\/td><\/tr>
    \u591a\u5e38\u91cf\u58f0\u660e<\/strong><\/td>\u53ef\u4ee5\u4f7f\u7528 const (...)<\/code> \u8fdb\u884c\u5206\u7ec4<\/td><\/tr>
    \u8ba1\u7b97<\/strong><\/td>\u5141\u8bb8\u7f16\u8bd1\u671f\u8ba1\u7b97\uff0c\u4f46\u4e0d\u652f\u6301\u8fd0\u884c\u65f6\u8ba1\u7b97<\/td><\/tr>
    iota<\/strong><\/td>\u7528\u4e8e\u81ea\u52a8\u9012\u589e\u5e38\u91cf\uff08\u4ece 0<\/code> \u5f00\u59cb\uff09<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
    \n","protected":false},"excerpt":{"rendered":"
    \u5728 Go \u8bed\u8a00\u4e2d\uff0c\u5e38\u91cf\uff08Constant\uff09 \u662f\u6307\u503c\u5728\u7a0b\u5e8f\u8fd0\u884c\u671f\u95f4\u4e0d\u4f1a\u53d1\u751f\u53d8\u5316\u7684\u53d8\u91cf\u3002Go \u8bed\u8a00\u4f7f\u7528 const […]<\/p>\n","protected":false},"author":1,"featured_media":3165,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[58],"tags":[],"class_list":["post-3164","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-golang"],"_links":{"self":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/3164","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/comments?post=3164"}],"version-history":[{"count":1,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/3164\/revisions"}],"predecessor-version":[{"id":3166,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/3164\/revisions\/3166"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/media\/3165"}],"wp:attachment":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/media?parent=3164"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/categories?post=3164"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/tags?post=3164"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}