{"id":207275,"date":"2025-07-08T09:24:12","date_gmt":"2025-07-08T01:24:12","guid":{"rendered":"https:\/\/server.hk\/cnblog\/207275\/"},"modified":"2025-07-08T09:24:12","modified_gmt":"2025-07-08T01:24:12","slug":"%e4%bd%bf%e7%94%a8%e5%8f%8d%e5%b0%84%e4%bb%8e%e6%b7%b1%e5%b1%82%e5%b5%8c%e5%a5%97%e7%bb%93%e6%9e%84%e4%b8%ad%e6%8f%90%e5%8f%96%e6%a0%87%e7%ad%be","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/207275\/","title":{"rendered":"\u4f7f\u7528\u53cd\u5c04\u4ece\u6df1\u5c42\u5d4c\u5957\u7ed3\u6784\u4e2d\u63d0\u53d6\u6807\u7b7e"},"content":{"rendered":"

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

\u5f53\u524d\u4f4d\u7f6e\uff1a ><\/span> ><\/span> ><\/span> ><\/span> \u4f7f\u7528\u53cd\u5c04\u4ece\u6df1\u5c42\u5d4c\u5957\u7ed3\u6784\u4e2d\u63d0\u53d6\u6807\u7b7e<\/span><\/p>\n

\u6765\u6e90\uff1astackoverflow<\/span>
\n2024-04-21 12:18:37<\/span>
\n<\/i>0\u6d4f\u89c8<\/span>
\n<\/i>\u6536\u85cf<\/span> <\/p>\n

\u4e00\u5206\u8015\u8018\uff0c\u4e00\u5206\u6536\u83b7\uff01\u65e2\u7136\u90fd\u6253\u5f00\u8fd9\u7bc7\u300a\u4f7f\u7528\u53cd\u5c04\u4ece\u6df1\u5c42\u5d4c\u5957\u7ed3\u6784\u4e2d\u63d0\u53d6\u6807\u7b7e\u300b<\/span>\uff0c\u5c31\u575a\u6301\u770b\u4e0b\u53bb\uff0c\u5b66\u4e0b\u53bb\u5427\uff01\u672c\u6587\u4e3b\u8981\u4f1a\u7ed9\u5927\u5bb6\u8bb2\u5230<\/span>\u7b49\u7b49\u77e5\u8bc6\u70b9\uff0c\u5982\u679c\u5927\u5bb6\u5bf9\u672c\u6587\u6709\u597d\u7684\u5efa\u8bae\u6216\u8005\u770b\u5230\u6709\u4e0d\u8db3\u4e4b\u5904\uff0c\u975e\u5e38\u6b22\u8fce\u5927\u5bb6\u79ef\u6781\u63d0\u51fa\uff01\u5728\u540e\u7eed\u6587\u7ae0\u6211\u4f1a\u7ee7\u7eed\u66f4\u65b0Golang<\/span>\u76f8\u5173\u7684\u5185\u5bb9\uff0c\u5e0c\u671b\u5bf9\u5927\u5bb6\u90fd\u6709\u6240\u5e2e\u52a9\uff01<\/p>\n

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

\u6211\u6b63\u5728\u5c1d\u8bd5\u4ece\u4e00\u4e9b\u6df1\u5c42\u5d4c\u5957\u7684\u7ed3\u6784\u4e2d\u63d0\u53d6\u4e00\u4e9b\u6807\u7b7e\u3002\u8fd9\u4e9b\u7ed3\u6784\u662f\u4ece protobuf \u6d88\u606f\u751f\u6210\u7684\uff0c\u5e76\u5305\u542b json \u6807\u7b7e\u3002 <\/p>\n

\u6211\u6709\u4e00\u4e2a\u6307\u5411\u7ed3\u6784\u7684\u6307\u9488\uff0c\u8be5\u7ed3\u6784\u53ef\u80fd\u5305\u542b\u4e00\u4e2a\u5e26\u6709\u6211\u53ef\u80fd\u60f3\u8981\u7684\u6807\u7b7e\u7684\u5b57\u6bb5\u7684\u7ed3\u6784\u3002\u6211\u53ef\u4ee5\u4f7f\u7528\u7c7b\u578b\u8fdb\u884c\u8fed\u4ee3\u6765\u83b7\u53d6\u7ed3\u6784\u4f53\u7684\u5b57\u6bb5\uff0c\u4f46\u662f\u5f53\u6211\u9047\u5230\u4e00\u4e2a\u6307\u9488\u5b57\u6bb5\u65f6\uff0c\u5982\u4f55\u83b7\u53d6\u5b83\u7684\u503c\u7136\u540e\u9012\u5f52\uff1f<\/p>\n

\/\/ Struct has hierarchy like this \na := &somepb.UpdateRequest{\n        Updates: []*somepb.UpdateRequest_Foo{\n            &somepb.UpdateRequest_Foo{\n                Id: 1,\n                Foo: &somepb.FooInfo{\n                    Metadata: &somepb.Metadata{\n                        Name:        \"Foo\",\n                        Description: \"Bar\",\n                    },\n                    Some:    \"s\",\n                    Things:  \"o\",\n                    Are:     \"m\",\n                    Broken:  \"e\",\n                    Here:    \"p\",\n                },\n            },\n        },\n } \n\n\/\/ ParseStruct parses struct tags of given object\nfunc ParseStruct(obj interface{}, tag string) {\n    r := reflect.ValueOf(obj)\n    if r.Kind() == reflect.Ptr {\n        obj = r.Elem().Interface()\n    }\n    rv := reflect.TypeOf(obj)\n    for i := 0; i < rv.NumField(); i++ {\n        f := rv.Field(i)\n        \/\/ This is to avoid getting tags for Metadata itself (from the struct above)\n        \/\/ which is *Metadata, I want the tags for Name and Description\n        \/\/ inside *Metadata instead\n        if f.Type.Kind() == reflect.Ptr {\n            value := f.Tag.Get(tag)\n            if len(value) == 0 {\n                continue\n            }\n            fmt.Println(value)\n        }\n    }\n}<\/pre>\n
 <\/p>\n
\u89e3\u51b3\u65b9\u6848<\/h2>\n
 <\/p>\n
reflect.type<\/code> \u548c reflect.value<\/code> \u90fd\u6709 elem()<\/code> \u65b9\u6cd5\u3002\u6839\u636e \uff0c<\/p>\n
type<\/code>\u7684elem<\/code>\u65b9\u6cd5\u3002<\/p>\n
\/\/ elem returns a type's element type.\n\/\/ it panics if the type's kind is not array, chan, map, ptr, or slice.\nelem() type<\/pre>\n
value.elem<\/code>\uff1a<\/p>\n
func (v value) elem() value\n\nelem returns the value that the interface v contains or that the pointer v points to. it panics if v's kind is not interface or ptr. it returns the zero value if v is nil.<\/pre>\n
\u53ef\u4ee5\u4f7f\u7528elem()<\/code>\u65b9\u6cd5\u83b7\u53d6\u6307\u9488\u7684\u5185\u5bb9\uff0c\u7136\u540e\u4f7f\u7528\u8be5\u5185\u5bb9\u8fdb\u884c\u9012\u5f52\u3002\u4f46\u662f\uff0c\u9274\u4e8e\u60a8\u7684\u539f\u59cb api \u662f func(interface{},string)<\/code>\uff0c\u60a8\u9700\u8981\u4f7f\u7528 value.elem().interface()<\/code> \u6765\u83b7\u53d6\u6709\u610f\u4e49\u7684 interface{}<\/code>\u3002\u4f46\u6211\u5efa\u8bae\u60a8\u66f4\u6539 api \u4ee5\u63a5\u53d7 reflect.type<\/code> – \u56e0\u4e3a\u8fd9\u5bf9\u4e8e\u6807\u7b7e\u63d0\u53d6\u6765\u8bf4\u662f\u6700\u6e05\u6670\u7684\u3002<\/p>\n
\u793a\u4f8b\u4ee3\u7801\uff1a<\/p>\n
func ParseStruct(t reflect.Type, tag string) {\n    if t.Kind() == reflect.Ptr {\n        t = t.Elm()\n    }\n    if t.Kind() != reflect.Struct {\n        return\n    }\n\n    for i := 0; i < t.NumField(); i++ {\n        f := t.Field(i)\n        value := f.Tag.Get(tag)\n        ft := t.Type\n        if ft.Kind() == reflect.Ptr {\n            ft = ft.Elem()\n        }\n\n        \/\/ It seems that you don't want a tag from an struct field; only other fields' tags are needed\n        if ft.Kind() != reflect.Struct {\n            if len(value) != 0 {\n                fmt.Println(value)\n            }\n            continue\n        }\n\n        ParseStruct(ft,tag)\n    }\n}<\/pre>\n
\u8bf7\u6ce8\u610f\uff0c\u6b64\u4ee3\u7801\u975e\u5e38\u7b80\u5355 – \u5b83\u4e0d\u5904\u7406\u5207\u7247\u6216\u6620\u5c04\u4e2d\u7684\u7ed3\u6784\u6807\u7b7e\u3002<\/p>\n
\u5f53\u4f60\u5728 reflect.value<\/code> \u6216 reflect.type<\/code> \u4e0a\u9047\u5230\u6307\u9488\u65f6\uff0c\u4f60\u5fc5\u987b\u4f7f\u7528 elem()<\/code> \u7ee7\u7eed\u524d\u8fdb\u3002<\/p>\n
reflect.valueof(new(string)).elem()<\/code> \u4ece\u503c *string<\/code> \u53d8\u4e3a string<\/code><\/p>\n
reflect.typeof(new(string)).elem()<\/code> \u4ece\u7c7b\u578b *string<\/code> \u53d8\u4e3a string<\/code><\/p>\n
\u7406\u8bba\u8981\u638c\u63e1\uff0c\u5b9e\u64cd\u4e0d\u80fd\u843d\uff01\u4ee5\u4e0a\u5173\u4e8e\u300a\u4f7f\u7528\u53cd\u5c04\u4ece\u6df1\u5c42\u5d4c\u5957\u7ed3\u6784\u4e2d\u63d0\u53d6\u6807\u7b7e\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-207275","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/207275","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=207275"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/207275\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=207275"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=207275"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=207275"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}