{"id":207769,"date":"2025-07-08T14:24:19","date_gmt":"2025-07-08T06:24:19","guid":{"rendered":"https:\/\/server.hk\/cnblog\/207769\/"},"modified":"2025-07-08T14:24:19","modified_gmt":"2025-07-08T06:24:19","slug":"%e4%b8%ba%e4%bb%80%e4%b9%88%e6%88%91%e7%9a%84-go-%e5%8d%8f%e7%a8%8b%e5%9c%a8%e5%a4%84%e7%90%86%e5%90%8e%e5%8d%a1%e4%bd%8f%e4%ba%86%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/207769\/","title":{"rendered":"\u4e3a\u4ec0\u4e48\u6211\u7684 go \u534f\u7a0b\u5728\u5904\u7406\u540e\u5361\u4f4f\u4e86\uff1f"},"content":{"rendered":"

<\/b> <\/p>\n

\u5f53\u524d\u4f4d\u7f6e\uff1a ><\/span> ><\/span> ><\/span> ><\/span> \u4e3a\u4ec0\u4e48\u6211\u7684 go \u534f\u7a0b\u5728\u5904\u7406\u540e\u5361\u4f4f\u4e86\uff1f<\/span><\/p>\n

\u6765\u6e90\uff1astackoverflow<\/span>
\n2024-04-25 15:00:37<\/span>
\n<\/i>0\u6d4f\u89c8<\/span>
\n<\/i>\u6536\u85cf<\/span> <\/p>\n

\u4f60\u5728\u5b66\u4e60Golang<\/span>\u76f8\u5173\u7684\u77e5\u8bc6\u5417\uff1f\u672c\u6587\u300a\u4e3a\u4ec0\u4e48\u6211\u7684 go \u534f\u7a0b\u5728\u5904\u7406\u540e\u5361\u4f4f\u4e86\uff1f\u300b<\/span>\uff0c\u4e3b\u8981\u4ecb\u7ecd\u7684\u5185\u5bb9\u5c31\u6d89\u53ca\u5230<\/span>\uff0c\u5982\u679c\u4f60\u60f3\u63d0\u5347\u81ea\u5df1\u7684\u5f00\u53d1\u80fd\u529b\uff0c\u5c31\u4e0d\u8981\u9519\u8fc7\u8fd9\u7bc7\u6587\u7ae0\uff0c\u5927\u5bb6\u8981\u77e5\u9053\u7f16\u7a0b\u7406\u8bba\u57fa\u7840\u548c\u5b9e\u6218\u64cd\u4f5c\u90fd\u662f\u4e0d\u53ef\u6216\u7f3a\u7684\u54e6\uff01<\/p>\n

\u95ee\u9898\u5185\u5bb9
\n <\/p>\n

\u6211\u662f golang \u65b0\u624b\u3002\u6211\u4e00\u76f4\u5728\u4f7f\u7528 gorm \u548c go \u7684\u5e76\u53d1\u6765\u8bfb\u53d6 sqlite \u6570\u636e\u5e93\u5e76\u5c06\u5176\u5199\u5165 csv \u6587\u4ef6\u3002\u5b83\u5de5\u4f5c\u987a\u5229\uff0c\u4f46\u662f\u5f53\u5904\u7406\u5b8c\u6210\u65f6\uff0c\u5b83\u5e76\u6ca1\u6709\u7ed3\u675f\u4e3b\u7a0b\u5e8f\u5e76\u9000\u51fa\u3002\u6211\u5fc5\u987b\u6253\u5370 command+c<\/code> \u624d\u80fd\u9000\u51fa\u3002\u6211\u4e0d\u77e5\u9053\u6211\u505a\u9519\u4e86\u4ec0\u4e48\u3002\u53ef\u80fd\u5b83\u6b63\u5728\u8fdb\u5165\u67d0\u79cd\u963b\u585e\u6216\u6b7b\u9501\u6a21\u5f0f\u6216\u5176\u4ed6\u6a21\u5f0f\u3002\u6b64\u5916\uff0c\u5b83\u4e5f\u4e0d\u6253\u5370\u518d\u89c1\u6d88\u606f\u3002\u8fd9\u610f\u5473\u7740\u5b83\u4ecd\u5728\u5c1d\u8bd5\u4ece\u901a\u9053\u8bfb\u53d6\u6570\u636e\u3002\u8bf7\u5e2e\u5fd9\u3002\u8fd9\u662f\u4ee3\u7801\u3002<\/p>\n

package main\n\nimport (\n    \"fmt\"\n    \"reflect\"\n\n    \"github.com\/jinzhu\/gorm\"\n    _ \"github.com\/jinzhu\/gorm\/dialects\/sqlite\"\n)\n\ntype AirQuality struct {\n    \/\/ gorm.Model\n    \/\/ ID      uint   `gorm:\"column:id\"`\n    Index   string `gorm:\"column:index\"`\n    BEN     string `gorm:\"column:BEN\"`\n    CH4     string `gorm:\"column:CH4\"`\n    CO      string `gorm:\"column:CO\"`\n    EBE     string `gorm:\"column:EBE\"`\n    MXY     string `gorm:\"column:MXY\"`\n    NMHC    string `gorm:\"column:NMHC\"`\n    NO      string `gorm:\"column:NO\"`\n    NO2     string `gorm:\"column:NO_2\"`\n    NOX     string `gorm:\"column:NOx\"`\n    OXY     string `gorm:\"column:OXY\"`\n    O3      string `gorm:\"column:O_3\"`\n    PM10    string `gorm:\"column:PM10\"`\n    PM25    string `gorm:\"column:PM25\"`\n    PXY     string `gorm:\"column:PXY\"`\n    SO2     string `gorm:\"column:SO_2\"`\n    TCH     string `gorm:\"column:TCH\"`\n    TOL     string `gorm:\"column:TOL\"`\n    Time    string `gorm:\"column:date; type:timestamp\"`\n    Station string `gorm:\"column:station\"`\n}\n\nfunc (AirQuality) TableName() string {\n    return \"AQ\"\n}\n\nfunc main() {\n    c := generateRows(\"boring!!\")\n    for {\n        fmt.Println(<-c)\n        if c == nil {\n            fmt.Println(\"Bye\")\n            break\n        }\n    }\n}\n\nfunc generateRows(msg string) <-chan []string {\n    c := make(chan []string)\n    go func() {\n        db, err := gorm.Open(\"sqlite3\", \".\/load_testing_7.6m.db\")\n        if err != nil {\n            panic(\"failed to connect database\")\n        }\n        defer db.Close()\n        rows, err := db.Model(&AirQuality{}).Limit(20).Rows()\n        defer rows.Close()\n        if err != nil {\n            panic(err)\n        }\n        for rows.Next() {\n            var aq AirQuality\n            db.ScanRows(rows, &aq)\n            v := reflect.Indirect(reflect.ValueOf(aq))\n            var buf []string\n            for i := 0; i < v.NumField(); i++ {\n                buf = append(buf, v.Field(i).String())\n            }\n            c <- buf\n        }\n    }()\n    return c\n}<\/pre>\n
 <\/p>\n
\u89e3\u51b3\u65b9\u6848<\/h2>\n
 <\/p>\n
\u4ece\u65e0\u7f13\u51b2\u7684\u901a\u9053\uff08\u4f8b\u5982\u60a8\u7684\u901a\u9053\uff09\u63a5\u6536\uff0c\u5176\u4e2d\u6ca1\u6709\u4eba\u51c6\u5907\u597d\u53d1\u9001\u503c\u5757\u3002\u8fd9\u5c31\u662f\u4f60\u6240\u7ecf\u5386\u7684\u3002 <\/p>\n
\u8868\u8fbe\u5f0f [<-c<\/code>] \u4f1a\u963b\u585e\uff0c\u76f4\u5230\u6709\u53ef\u7528\u503c\u4e3a\u6b62\u3002<\/p>\n
\u5728\u901a\u9053\u4e2d\u53d1\u51fa\u201ceof\u201d\u4fe1\u53f7\u7684\u5e38\u89c1\u65b9\u6cd5\u662f\uff0c\u5f53\u6ca1\u6709\u66f4\u591a\u503c\u8981\u53d1\u9001\u65f6\uff0c\u4f7f\u7528\u5185\u7f6e\u7684 \u51fd\u6570\u4ece\u53d1\u9001\u65b9\u5173\u95ed\u901a\u9053\u3002<\/p>\n
\u5c1d\u8bd5\u4ece\u5173\u95ed\u7684\u901a\u9053\u63a5\u6536\u6570\u636e\u53ef\u4ee5\u7acb\u5373\u8fdb\u884c\uff0c\u4ea7\u751f\u901a\u9053\u5143\u7d20\u7c7b\u578b\u7684 \u3002\u8981\u68c0\u6d4b\u6b64\u201c\u5173\u95ed\u201d\u72b6\u6001\uff0c\u8bf7\u4f7f\u7528\u7279\u6b8a\u7684\u9017\u53f7-ok \u4e60\u60ef\u7528\u6cd5\uff1a<\/p>\n
value, ok := <- c<\/pre>\n
\u5982\u679c\u901a\u9053\u5173\u95ed\uff0cok<\/code> \u5c06\u4e3a false<\/code>\uff08\u5426\u5219\u4e3a true<\/code>\uff09\u3002<\/p>\n
\u201c\u8017\u5c3d\u201d\u901a\u9053\u76f4\u81f3\u5176\u5173\u95ed\u7684\u7b80\u5355\u4e14\u6b63\u786e\u7684\u65b9\u6cd5\u662f\u4f7f\u7528 for range<\/code> \u5faa\u73af\uff0c\u5982\u4e0b\u6240\u793a\uff1a<\/p>\n
for value := range c {\n    fmt.println(\"received:\", value)\n}<\/pre>\n
\u4e00\u65e6\u4ece\u901a\u9053 c<\/code> \u63a5\u6536\u5230\u5173\u95ed\u4e4b\u524d\u5728\u5176\u4e0a\u53d1\u9001\u7684\u6240\u6709\u503c\uff0cfor range<\/code> \u5c31\u4f1a\u7ec8\u6b62\u3002<\/p>\n
\u6240\u4ee5\u5728 generaterows()<\/code> \u4e2d\uff0c\u6267\u884c\u4ee5\u4e0b\u64cd\u4f5c\uff1a<\/p>\n
go func() {\n    \/\/ \/\/ use defer so it will be closed no matter how this function call ends\n    defer close(c)\n    \/\/ ...\n}()<\/pre>\n
\u8fd8\u6709\u4f60\u7684 main()<\/code>:<\/p>\n
func main() {\n    c := generateRows(\"boring!!\")\n    for v := range c {\n        fmt.Println(v)\n    }\n    fmt.Println(\"Bye\")\n}<\/pre>\n
\u7406\u8bba\u8981\u638c\u63e1\uff0c\u5b9e\u64cd\u4e0d\u80fd\u843d\uff01\u4ee5\u4e0a\u5173\u4e8e\u300a\u4e3a\u4ec0\u4e48\u6211\u7684 go \u534f\u7a0b\u5728\u5904\u7406\u540e\u5361\u4f4f\u4e86\uff1f\u300b\u7684\u8be6\u7ec6\u4ecb\u7ecd\uff0c\u5927\u5bb6\u90fd\u638c\u63e1\u4e86\u5427\uff01\u5982\u679c\u60f3\u8981\u7ee7\u7eed\u63d0\u5347\u81ea\u5df1\u7684\u80fd\u529b\uff0c\u90a3\u4e48\u5c31\u6765\u5173\u6ce8\u516c\u4f17\u53f7\u5427\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"
\u5f53\u524d\u4f4d\u7f6e\uff1a > > ...<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4925],"tags":[],"class_list":["post-207769","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/207769","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=207769"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/207769\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=207769"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=207769"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=207769"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}