{"id":130,"date":"2013-07-26T20:37:10","date_gmt":"2013-07-26T12:37:10","guid":{"rendered":"http:\/\/coderbee.net\/?p=130"},"modified":"2013-07-26T20:38:33","modified_gmt":"2013-07-26T12:38:33","slug":"go%e8%af%ad%e8%a8%80%e5%9f%ba%e7%a1%80","status":"publish","type":"post","link":"https:\/\/coderbee.net\/index.php\/go\/20130726\/130","title":{"rendered":"Go\u8bed\u8a00\u57fa\u7840"},"content":{"rendered":"

\u5206\u53f7<\/strong> : \u5982\u679c\u5e0c\u671b\u5c06\u4e24\u4e2a\u6216\u591a\u4e2a\u8bed\u53e5\u653e\u5728\u540c\u4e00\u884c\uff0c\u5fc5\u987b\u7528\u5206\u53f7\u5206\u9694\uff1b\u4e00\u822c\u60c5\u51b5\u4e0b\uff0c\u4e0d\u9700\u8981\u5206\u53f7\u3002<\/p>\n

\u5305<\/h2>\n

Go\u7a0b\u5e8f\u662f\u901a\u8fc7\u5305\u6765\u7ec4\u7ec7\u7684\uff0c\u5305\u540d\u4e3amain<\/code>\u7684\u662f\u4e00\u4e2a\u53ef\u72ec\u7acb\u8fd0\u884c\u7684\u5305\uff0c\u7f16\u8bd1\u540e\u4ea7\u751f\u53ef\u6267\u884c\u6587\u4ef6\u3002main<\/code>\u5305\u7684main<\/code>\u51fd\u6570\u662f\u7a0b\u5e8f\u7684\u5165\u53e3\uff0c\u662f\u4e2a\u6ca1\u6709\u53c2\u6570\u4e5f\u6ca1\u6709\u8fd4\u56de\u503c\u7684\u51fd\u6570\u3002<\/p>\n

\u53ef\u4ee5\u4f7f\u7528GOPATH<\/code>\u73af\u5883\u53d8\u91cf\u6216\u662f\u4f7f\u7528\u76f8\u5bf9\u8def\u5f84\u6765import\u81ea\u5b9a\u4e49\u7684package\u3002Go\u7ea6\u5b9a\u5982\u4e0b\uff1a
\n 1. \u5728import\u4e2d\uff0c\u53ef\u4ee5\u4f7f\u7528\u76f8\u5bf9\u8def\u5f84\u5982.\/<\/code>\u6216 ..\/<\/code>\u6765\u5f15\u7528\u81ea\u5b9a\u4e49\u5305\uff1b
\n 2. \u5982\u679c\u6ca1\u6709\u4f7f\u7528\u76f8\u5bf9\u8def\u5f84\uff0c\u90a3\u4e48Go\u4f1a\u53bb$GOPATH\/src\/<\/code>\u76ee\u5f55\u67e5\u627e\u3002
\n<\/p>\n

\u53d8\u91cf\u4e0e\u5e38\u91cf<\/h2>\n

\u53d8\u91cf\u58f0\u660e<\/h3>\n
    \n
  1. \u7c7b\u578b\u662f\u540e\u7f00\u7684\uff0c\u6709\u65f6\u53ef\u4ee5\u7701\u7565\uff1b<\/li>\n
  2. \u4ee5var\u5173\u952e\u5b57\u5f00\u5934\uff0c\u6709\u65f6\u53ef\u4ee5\u7701\u7565\u7684\uff1b<\/li>\n
  3. \u81ea\u52a8\u7c7b\u578b\u63a8\u65ad\uff1b<\/li>\n
  4. \u53ef\u4ee5\u5e73\u884c\u5b9a\u4e49\u591a\u4e2a\u53d8\u91cf\uff1b<\/li>\n<\/ol>\n

    \u4e3e\u4f8b\uff1a<\/p>\n

    \nvar count int                                   \/\/ \u58f0\u660e\nvar total  int = 42                            \/\/ \u58f0\u660e\u5e76\u521d\u59cb\u5316\nvar total,  avg int  =  42,  20             \/\/ \u540c\u65f6\u58f0\u660e\u5e76\u521d\u59cb\u5316\u591a\u4e2a\u53d8\u91cf\nvar a, b * int                                   \/\/ \u58f0\u660e\u4e24\u4e2aint\u7c7b\u578b\u6307\u9488\nvar label = \"string value\"                  \/\/ \u7701\u7565\u4e86\u7c7b\u578b\uff0c\u7f16\u8bd1\u5668\u81ea\u52a8\u63a8\u65ad\ni := 123                                          \/\/ \u5b9a\u4e49\u5e76\u521d\u59cb\u5316\ni, str := 123\uff0c \"string value\"             \/\/ \u5e73\u884c\u5b9a\u4e49\uff0c\u8fd8\u53ef\u7528\u7528\u51fd\u6570\u7684\u8fd4\u56de\u503c\u6765\u5b9a\u4e49\n<\/code><\/pre>\n
    :=<\/code>\u53ea\u80fd\u5728\u51fd\u6570\u5185\u90e8\u4f7f\u7528\uff0c\u5728\u51fd\u6570\u5916\u4f7f\u7528\u4f1a\u51fa\u73b0\u7f16\u8bd1\u9519\u8bef\uff1b\u4e00\u822c\u7528var<\/code>\u65b9\u5f0f\u5b9a\u4e49\u5168\u5c40\u53d8\u91cf\u3002<\/p>\n
    \u591a\u4e2avar\u58f0\u660e\u53ef\u4ee5\u6210\u7ec4\uff0c\u7ec4\u7528\u5c0f\u62ec\u53f7\uff0cconst\u548cimport\u4e5f\u8fd9\u6837\u505a\u3002\u5982\uff1a<\/p>\n
    \nimport(\n    \"fmt\"\n    \"os\"\n)\n\nconst(\n    i = 100\n    pi = 3.1415\n    prefix = \"Go_\"\n)\n\nvar(\n    i  int\n    pi  float32\n    prefix  string\n)\n<\/code><\/pre>\n
    \u5f53\u5b9a\u4e49\u4e00\u4e2a\u53d8\u91cf\u65f6\uff0c\u5b83\u9ed8\u8ba4\u8d4b\u503c\u4e3a\u5176\u7c7b\u578b\u7684null<\/code>\u503c\u3002\u5982\uff0cvar a int<\/code>\uff0ca<\/code>\u7684\u503c\u662f0<\/code>\uff0cvar s string<\/code>\uff0c s<\/code>\u88ab\u8d4b\u503c\u4e3a\u96f6\u957f\u5ea6\u7684\u5b57\u7b26\u4e32\uff0c\u4e5f\u5c31\u662f\"\"<\/code> \u3002<\/p>\n
    \u4e00\u4e2a\u7279\u6b8a\u7684\u53d8\u91cf\u540d\u662f _<\/code> \uff08\u4e0b\u5212\u7ebf\uff09\uff0c\u4efb\u4f55\u8d4b\u503c\u7ed9\u5b83\u7684\u503c\u90fd\u88ab\u4e22\u5f03\u3002\u6240\u4ee5 _<\/code> \u53ef\u4ee5\u8bf4\u662f\u5c5e\u4e8e\u4efb\u4f55\u7c7b\u578b\u7684\u3002<\/p>\n
    \u58f0\u660e\u4f46\u672a\u4f7f\u7528\u7684\u53d8\u91cf\u5728\u7f16\u8bd1\u65f6\u5c06\u62a5\u9519\u3002<\/p>\n
    ###  \u5e38\u91cf
    \n\u5e38\u91cf\u5728\u7f16\u8bd1\u65f6\u88ab\u521b\u5efa\uff0c\u53ea\u80fd\u662f\u6570\u5b57\u3001\u5b57\u7b26\u4e32\u6216\u5e03\u5c14\u503c\u3002<\/p>\n
    \nconst (\n    a = iota\n    b = iota\n)\n<\/code><\/pre>\n
    iota<\/code>\u53ef\u4ee5\u751f\u6210\u6570\u503c\u7684\u9012\u589e\u7684\u679a\u4e3e\u503c\u3002iota<\/code>\u7b2c\u4e00\u6b21\u4f7f\u7528\u65f6\u662f0\uff0c\u4ee5\u540e\u6bcf\u6b21\u4f7f\u7528\u503c\u589e\u52a01\u3002<\/p>\n
    \nconst (\n    a = iota\n    b           \/\/ \u9690\u5f0f\u7684 b = iota\n    b string  \/\/ \u660e\u786e\u6307\u5b9a\u7c7b\u578b\n)\n<\/code><\/pre>\n
    \u6570\u636e\u7c7b\u578b<\/h2>\n
    \u5e03\u5c14\u7c7b\u578b<\/h3>\n
    \u5e03\u5c14\u7c7b\u578b\u8868\u793a\u7531\u9884\u5b9a\u4e49\u5e38\u91cftrue<\/code>\u548cfalse<\/code>\u4ee3\u8868\u7684\u5e03\u5c14\u5224\u5b9a\u503c\u3002\u5e03\u5c14\u7c7b\u578b\u662fbool<\/code>\u3002<\/p>\n
    \u6570\u5b57\u7c7b\u578b<\/h3>\n
    int \u548c uint\u7c7b\u578b\u7684\u957f\u5ea6\u53d6\u51b3\u4e8e\u786c\u4ef6\u5e73\u53f0\u3002\u4f46\u53ea\u4f1a\u662f32\u621664\u4f4d\u4e4b\u4e00\u3002<\/p>\n
    \u5b8c\u6574\u7684\u6574\u6570\u7c7b\u578b\u5217\u8868\uff1a
    \n\u6709\u7b26\u53f7\uff1a int8, int16, int 32, int64
    \n\u65e0\u7b26\u53f7\uff1a byte, uint8, uint16, uint32, uint64\u3002
    \nrune \u662fint32\u7684\u522b\u540d\uff0cbyte\u662fuint8\u7684\u522b\u540d\u3002<\/p>\n
    \u6d6e\u70b9\u7c7b\u578b\u7684\u503c\u6709float32\u548cfloat64\u3002\uff08\u6ca1\u6709float\u7c7b\u578b\uff09<\/p>\n
    64\u4f4d\u7684\u6574\u6570\u548c\u6d6e\u70b9\u6570\u603b\u662f64\u4f4d\u7684\uff0c\u5373\u4f7f\u662f\u572832\u4f4d\u7684\u67b6\u6784\u4e0a\u3002<\/p>\n
    \u8fd9\u4e9b\u7c7b\u578b\u90fd\u662f\u72ec\u7acb\u7684\uff0c\u6df7\u5408\u4f7f\u7528\u8fd9\u4e9b\u7c7b\u578b\u5411\u53d8\u91cf\u8d4b\u503c\u4f1a\u5f15\u8d77\u7f16\u8bd1\u5668\u9519\u8bef\u3002<\/p>\n
    rune<\/h3>\n
    rune \u662fint32\u7684\u522b\u540d\uff0c\u7528UTF-8<\/code>\u7f16\u7801\u3002 \u5728\u9700\u8981\u904d\u5386\u5b57\u7b26\u4e32\u4e2d\u7684\u5b57\u7b26\uff0c\u4e3a\u4e86\u83b7\u5f97\u5b9e\u9645\u7684\u5b57\u7b26\uff0c\u9700\u8981\u4f7f\u7528rune\u7c7b\u578b\u3002<\/p>\n
    string<\/h3>\n
    \u5b57\u7b26\u4e32\u662f\u7528\u53cc\u5f15\u53f7\u6216\u53cd\u5f15\u53f7\u5305\u88f9\u7684\u5b57\u7b26\u5e8f\u5217\uff0c\u662f\u4e0d\u53ef\u53d8\u7684\uff0cUTF-8<\/code>\u7f16\u7801\u3002\u53ef\u4ee5\u7528+<\/code>\u64cd\u4f5c\u7b26\u6765\u8fde\u63a5\u4e24\u4e2a\u5b57\u7b26\u4e32\u3002<\/p>\n
    \u7528\u53cd\u5f15\u53f7\u4f5c\u4e3a\u539f\u59cb\u5b57\u7b26\u4e32\u7b26\u53f7\uff1a
    \n<pre><code>
    \ns :=<\/code>start part
    \nending part`
    \n<\/code>
    \n\u73b0\u5728s\u5305\u542b\u6362\u884c\u3002<\/p>\n
    \u4e0d\u50cf\u8f6c\u4e49\u5b57\u7b26\u4e32\u6807\u8bc6\uff0c\u539f\u59cb\u5b57\u7b26\u4e32\u6807\u8bc6\u7684\u503c\u5728\u5f15\u53f7\u5185\u7684\u5b57\u7b26\u662f\u4e0d\u8f6c\u4e49\u7684\u3002<\/p>\n
    \u590d\u6570<\/h3>\n
    Go\u539f\u751f\u652f\u6301\u590d\u6570\uff0ccomplex128\u548ccomplex64\uff0c\u865a\u6570\u90e8\u5206\u5206\u522b\u670964\u300132\u4f4d\u3002\u590d\u6570\u5199\u4e3a\uff1aRE + IMi<\/code>\uff0cRE\u662f\u5b9e\u6570\u90e8\u5206\uff0cIM\u662f\u865a\u6570\u90e8\u5206\u3002<\/p>\n
    \n    var comp complex64 = 4 + 5i\n    fmt.Printf(\"value is : %v\", comp)\n<\/code><\/pre>\n
    \u5c06\u6253\u5370 (4+5i)<\/code><\/p>\n
    \u7c7b\u578b\u8f6c\u6362<\/h3>\n
    Go\u4e0d\u652f\u6301\u9690\u5f0f\u7684\u7c7b\u578b\u8f6c\u6362\uff0c\u6240\u6709\u7684\u7c7b\u578b\u8f6c\u6362\u90fd\u5fc5\u987b\u662f\u663e\u5f0f\u7684\u3002\u7c7b\u578b\u8f6c\u6362\u7684\u65b9\u5f0f\uff1av  dstType  :=  dstType(srcVal)<\/code>\u3002<\/p>\n
    \nbytes []byte := []byte(\"string value\")          \/\/ \u5b57\u7b26\u4e32\u5230\u5b57\u8282\u6570\u7ec4\u7684\u8f6c\u6362\nstr := string(bytes)                                   \/\/ \u5b57\u8282\u6570\u7ec4\u5230\u5b57\u7b26\u4e32\u7684\u8f6c\u6362\nui := uint32(-128)                                     \/\/ \u6709\u7b26\u53f7\u6570\u5230\u65e0\u7b26\u53f7\u6570\u7684\u663e\u5f0f\u8f6c\u6362\n<\/code><\/pre>\n
    \u8fd0\u7b97\u7b26<\/h2>\n
    \"go-operator\"<\/a><\/p>\n
    \u8868\u683c\u4e2d\u6ca1\u6709\u5217\u51fa\u7684\u8fd8\u6709\u903b\u8f91\u975e !<\/code>\u3002<\/p>\n
    &^<\/code> \u8868\u793a\u4f4d\u6e05\u9664\u3002<\/p>\n
    \u8fd0\u7b97\u7b26\u90fd\u662f\u4ece\u5de6\u5230\u53f3\u7ed3\u5408\u7684\u3002Go\u4e0d\u652f\u6301\u8fd0\u7b97\u7b26\u91cd\u8f7d\u3002<\/p>\n
    Go\u4fdd\u7559\u5b57<\/h2>\n
    \"go-reserve-keyword\"<\/a><\/p>\n
    array\u3001slices\u3001map<\/h2>\n
    array<\/h3>\n
    array \u7531[len]type<\/code> \u5b9a\u4e49\uff0clen\u8868\u793a\u6570\u7ec4\u7684\u957f\u5ea6\uff0ctype\u8868\u793a\u5b58\u50a8\u5143\u7d20\u7684\u7c7b\u578b\u3002\u5bf9array\u5143\u7d20\u7684\u8d4b\u503c\u6216\u7d22\u5f15\u662f\u7531\u62ec\u53f7[]<\/code>\u5b8c\u6210\u7684\u3002<\/p>\n
    \nvar arr [10]int\narr[0] = 43\narr[1] = 20\n<\/code><\/pre>\n
    \u5927\u5c0f\u662f\u7c7b\u578b\u7684\u4e00\u90e8\u5206\uff0c\u4e0d\u540c\u5927\u5c0f\u7684\u662f\u4e0d\u540c\u7c7b\u578b\uff0c\u56e0\u6b64\u4e0d\u80fd\u6539\u53d8\u5927\u5c0f\u3002<\/p>\n
    \u6570\u7ec4\u540c\u6837\u662f\u503c\u7c7b\u578b\uff0c\u5c06\u4e00\u4e2a\u6570\u7ec4\u8d4b\u503c\u7ed9\u53e6\u4e00\u4e2a\u6570\u7ec4\uff0c\u4f1a\u590d\u5236\u6240\u6709\u7684\u5143\u7d20\u3002\u5f53\u5411\u51fd\u6570\u5185\u4f20\u9012\u4e00\u4e2a\u6570\u7ec4\u7684\u65f6\u5019\uff0c\u5b83\u4f1a\u83b7\u5f97\u4e00\u4e2a\u6570\u7ec4\u7684\u526f\u672c\uff0c\u800c\u4e0d\u662f\u6570\u7ec4\u7684\u6307\u9488\u3002<\/p>\n
    []<\/code>\u5185\u53ef\u663e\u793a\u6307\u5b9a\u6570\u7ec4\u957f\u5ea6\uff0c\u4e5f\u53ef\u7528 ...<\/code> \u4ee3\u66ff\uff0c\u5728{}<\/code>\u91cc\u5199\u6570\u7ec4\u5143\u7d20\uff0c\u4f7f\u75283\u4e2a\u53e5\u70b9\u65f6\uff0cGo\u81ea\u52a8\u8ba1\u7b97\u6570\u7ec4\u5143\u7d20\u7684\u4e2a\u6570\u3002<\/p>\n
    \na := []int {1, 2, 3}                         \/\/ \u58f0\u660e\u4e86\u957f\u5ea6\u4e3a3\u7684\u6570\u7ec4\nb := [10]int{1, 2, 3}                      \/\/ \u58f0\u660e\u4e86\u957f\u5ea6\u4e3a10\u7684\u6570\u7ec4\uff0c\u524d3\u4e2a\u5143\u7d20\u7684\u503c\u5206\u522b\u4e3a1,2,3\uff0c\u5176\u4f59\u5143\u7d20\u7684\u503c\u4e3a0\u3002\nc := [...]int{4, 5, 6}                       \/\/ \u91c7\u7528`...`\u7684\u65b9\u5f0f\uff0cGo\u6839\u636e\u5143\u7d20\u4e2a\u6570\u6765\u8ba1\u7b97\u6570\u7ec4\u957f\u5ea6\u3002\n\na2 := [2][2]int{ [...]int{4, 5}, [...]int{8,9} }          \/\/ \u4e8c\u7ef4\u6570\u7ec4\na3 := [2][2]int{ {4, 5}, {8,9} }                            \/\/ \u4e8c\u7ef4\u6570\u7ec4\uff0c\u7b80\u5316\u7684\u58f0\u660e\u65b9\u5f0f\n<\/code><\/pre>\n
    slice<\/h3>\n
    slice\u4e0earray\u63a5\u8fd1\uff0c\u4f46\u5728\u65b0\u7684\u5143\u7d20\u52a0\u5165\u7684\u65f6\u5019\u53ef\u4ee5\u589e\u52a0\u957f\u5ea6\u3002slice\u603b\u662f\u6307\u5411\u5e95\u5c42\u7684\u4e00\u4e2a\u6570\u7ec4\u3002slice\u662f\u4e00\u4e2a\u6307\u5411\u6570\u7ec4\u7684\u6307\u9488\uff0c\u662f\u5f15\u7528\u7c7b\u578b\u3002slice\u603b\u662f\u4e0e\u4e00\u4e2a\u56fa\u5b9a\u957f\u5ea6\u7684array\u6210\u5bf9\u51fa\u73b0\uff0c\u5176\u5f71\u54cdslice\u7684\u5bb9\u91cf\u548c\u957f\u5ea6\u3002<\/p>\n
    \u5207\u7247\u53ef\u4ee5\u5728\u6570\u7ec4\u6216\u5df2\u6709\u5207\u7247\u4e0a\u521b\u5efa\uff1avar  s =  arr[start : end]<\/code>\uff0c\u533a\u95f4\u4e3a\uff1a[start,  end)<\/code>\uff0cstart\u548cend\u90fd\u53ef\u4ee5\u7701\u7565\uff0c\u5192\u53f7:<\/code>\u4e0d\u80fd\u7701\u7565\uff0cstart\u9ed8\u8ba4\u4e3a0\uff0cend\u9ed8\u8ba4\u4e3a\u6570\u7ec4\u6216\u5207\u7247\u7684\u957f\u5ea6\u3002<\/p>\n
    s1 := make([]int, 10)<\/code> \u521b\u5efa\u4e00\u4e2a\u4fdd\u5b5810\u4e2a\u5143\u7d20\u7684slice\u3002<\/p>\n
    \nvar  s  []int                         \/\/  \u58f0\u660e\u4e00\u4e2aslice\uff0c\u4e0d\u9700\u8981\u957f\u5ea6\u3002\ns  :=  []byte{'a', 'b', 'c'}       \/\/  \u58f0\u660e\u5e76\u521d\u59cb\u5316\u3002\n\nvar array = [10]byte {'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j'}     \/\/  \u58f0\u660e\u4e00\u4e2a\u6570\u7ec4\n\nsa :=  array[:]                      \/\/  \u5b9a\u4e49\u4e00\u4e2aslice\uff0c\u5b83\u7684\u5143\u7d20\u662f\u6570\u7ec4ar\u7684\u6240\u6709\u5143\u7d20\u3002\naSlice := array[:3]                \/\/ \u7b49\u4ef7\u4e8eaSlice = array[0:3] aSlice\u5305\u542b\u5143\u7d20: a,b,c\naSlice := array[5:]                \/\/ \u7b49\u4ef7\u4e8eaSlice = array[5:10] aSlice\u5305\u542b\u5143\u7d20: f,g,h,i,j\naSlice := array[:]                  \/\/ \u7b49\u4ef7\u4e8eaSlice = array[0:10] \u8fd9\u6837aSlice\u5305\u542b\u4e86\u5168\u90e8\u7684\u5143\u7d20\n\nvar arr[m] int\nslice := arr[0 : n]\n\u6b64\u65f6\uff0clen(slice) == cap(slice) == n\nlen(arr) == len(arr) == m\n<\/code><\/pre>\n
    \u5bf9\u4e8eslice\u6709\u51e0\u4e2a\u6709\u7528\u7684\u5185\u7f6e\u51fd\u6570\uff1a<\/p>\n