{"id":7493,"date":"2020-04-03T11:13:40","date_gmt":"2020-04-03T03:13:40","guid":{"rendered":"https:\/\/kyle.ai\/blog\/?p=7493"},"modified":"2020-04-03T11:23:35","modified_gmt":"2020-04-03T03:23:35","slug":"golang-%e4%b8%ad%e4%bd%bf%e7%94%a8-json-%e7%9a%84%e5%b0%8f%e6%8a%80%e5%b7%a7","status":"publish","type":"post","link":"https:\/\/kyle.ai\/blog\/7493.html","title":{"rendered":"Golang \u4e2d\u4f7f\u7528 JSON \u7684\u5c0f\u6280\u5de7"},"content":{"rendered":"

\u4e34\u65f6\u5ffd\u7565struct\u7a7a\u5b57\u6bb5<\/h3>\n
type User struct {\n    Email    string `json:\"email\"`\n    Password string `json:\"password\"`\n    \/\/ many more fields\u2026\n}\n<\/code><\/pre>\n
\u5982\u679c\u60f3\u4e34\u65f6\u5ffd\u7565\u6389\u7a7aPassword<\/code>\u5b57\u6bb5,\u53ef\u4ee5\u7528omitempty<\/code>:<\/p>\n
json.Marshal(struct {\n    *User\n    Password bool `json:\"password,omitempty\"`\n}{\n    User: user,\n})\n<\/code><\/pre>\n
\u4e34\u65f6\u6dfb\u52a0\u989d\u5916\u7684\u5b57\u6bb5<\/h3>\n
type User struct {\n    Email    string `json:\"email\"`\n    Password string `json:\"password\"`\n    \/\/ many more fields\u2026\n}\n<\/code><\/pre>\n
\u4e34\u65f6\u5ffd\u7565\u6389\u7a7aPassword<\/code>\u5b57\u6bb5\uff0c\u5e76\u4e14\u6dfb\u52a0token<\/code>\u5b57\u6bb5<\/p>\n
json.Marshal(struct {\n    *User\n    Token    string `json:\"token\"`\n    Password bool `json:\"password,omitempty\"`\n}{\n    User: user,\n    Token: token,\n})\n<\/code><\/pre>\n
\u4e34\u65f6\u7c98\u5408\u4e24\u4e2astruct<\/h3>\n
\u901a\u8fc7\u5d4c\u5165struct\u7684\u65b9\u5f0f:<\/p>\n
type BlogPost struct {\n    URL   string `json:\"url\"`\n    Title string `json:\"title\"`\n}\n\ntype Analytics struct {\n    Visitors  int `json:\"visitors\"`\n    PageViews int `json:\"page_views\"`\n}\n\njson.Marshal(struct{\n    *BlogPost\n    *Analytics\n}{post, analytics})\n<\/code><\/pre>\n
\u4e00\u4e2ajson\u5207\u5206\u6210\u4e24\u4e2astruct<\/h3>\n
json.Unmarshal([]byte(`{\n  \"url\": \"attila@attilaolah.eu\",\n  \"title\": \"Attila's Blog\",\n  \"visitors\": 6,\n  \"page_views\": 14\n}`), &struct {\n  *BlogPost\n  *Analytics\n}{&post, &analytics})\n<\/code><\/pre>\n
\u4e34\u65f6\u6539\u540dstruct\u7684\u5b57\u6bb5<\/h3>\n
type CacheItem struct {\n    Key    string `json:\"key\"`\n    MaxAge int    `json:\"cacheAge\"`\n    Value  Value  `json:\"cacheValue\"`\n}\n\njson.Marshal(struct{\n    *CacheItem\n\n    \/\/ Omit bad keys\n    OmitMaxAge omit `json:\"cacheAge,omitempty\"`\n    OmitValue  omit `json:\"cacheValue,omitempty\"`\n\n    \/\/ Add nice keys\n    MaxAge int    `json:\"max_age\"`\n    Value  *Value `json:\"value\"`\n}{\n    CacheItem: item,\n\n    \/\/ Set the int by value:\n    MaxAge: item.MaxAge,\n\n    \/\/ Set the nested struct by reference, avoid making a copy:\n    Value: &item.Value,\n})\n<\/code><\/pre>\n
\u7528\u5b57\u7b26\u4e32\u4f20\u9012\u6570\u5b57<\/h3>\n
type TestObject struct {\n    Field1 int    `json:\",string\"`\n}\n<\/code><\/pre>\n
\u8fd9\u4e2a\u5bf9\u5e94\u7684json\u662f {\"Field1\": \"100\"}<\/code><\/p>\n
\u5982\u679cjson\u662f {\"Field1\": 100}<\/code> \u5219\u4f1a\u62a5\u9519<\/p>\n
\u5bb9\u5fcd\u5b57\u7b26\u4e32\u548c\u6570\u5b57\u4e92\u8f6c<\/h3>\n
\u5982\u679c\u4f60\u4f7f\u7528\u7684\u662fjsoniter\uff0c\u53ef\u4ee5\u542f\u52a8\u6a21\u7cca\u6a21\u5f0f<\/strong>\u6765\u652f\u6301 PHP \u4f20\u9012\u8fc7\u6765\u7684 JSON\u3002<\/p>\n
import \"github.com\/json-iterator\/go\/extra\"\n\nextra.RegisterFuzzyDecoders()\n<\/code><\/pre>\n
\u8fd9\u6837\u5c31\u53ef\u4ee5\u5904\u7406\u5b57\u7b26\u4e32\u548c\u6570\u5b57\u7c7b\u578b\u4e0d\u5bf9\u7684\u95ee\u9898\u4e86\u3002\u6bd4\u5982<\/p>\n
var val string\njsoniter.UnmarshalFromString(`100`, &val)\n<\/code><\/pre>\n
\u53c8\u6bd4\u5982<\/p>\n
var val float32\njsoniter.UnmarshalFromString(`\"1.23\"`, &val)\n<\/code><\/pre>\n
\u5bb9\u5fcd\u7a7a\u6570\u7ec4\u4f5c\u4e3a\u5bf9\u8c61<\/h3>\n
PHP\u53e6\u5916\u4e00\u4e2a\u4ee4\u4eba\u5d29\u6e83\u7684\u5730\u65b9\u662f\uff0c\u5982\u679c PHP array\u662f\u7a7a\u7684\u65f6\u5019\uff0c\u5e8f\u5217\u5316\u51fa\u6765\u662f[]<\/code>\u3002\u4f46\u662f\u4e0d\u4e3a\u7a7a\u7684\u65f6\u5019\uff0c\u5e8f\u5217\u5316\u51fa\u6765\u7684\u662f{\"key\":\"value\"}<\/code>\u3002 \u6211\u4eec\u9700\u8981\u628a []<\/code> \u5f53\u6210 {}<\/code> \u5904\u7406\u3002<\/p>\n
\u5982\u679c\u4f60\u4f7f\u7528\u7684\u662fjsoniter\uff0c\u53ef\u4ee5\u542f\u52a8\u6a21\u7cca\u6a21\u5f0f\u6765\u652f\u6301 PHP \u4f20\u9012\u8fc7\u6765\u7684 JSON\u3002<\/p>\n
import \"github.com\/json-iterator\/go\/extra\"\n\nextra.RegisterFuzzyDecoders()\n<\/code><\/pre>\n
\u8fd9\u6837\u5c31\u53ef\u4ee5\u652f\u6301\u4e86<\/p>\n
var val map[string]interface{}\njsoniter.UnmarshalFromString(`[]`, &val)\n<\/code><\/pre>\n
\u4f7f\u7528 MarshalJSON\u652f\u6301time.Time<\/h3>\n
golang \u9ed8\u8ba4\u4f1a\u628a time.Time<\/code> \u7528\u5b57\u7b26\u4e32\u65b9\u5f0f\u5e8f\u5217\u5316\u3002\u5982\u679c\u6211\u4eec\u60f3\u7528\u5176\u4ed6\u65b9\u5f0f\u8868\u793a time.Time<\/code>\uff0c\u9700\u8981\u81ea\u5b9a\u4e49\u7c7b\u578b\u5e76\u5b9a\u4e49 MarshalJSON<\/code>\u3002<\/p>\n
type timeImplementedMarshaler time.Time\n\nfunc (obj timeImplementedMarshaler) MarshalJSON() ([]byte, error) {\n    seconds := time.Time(obj).Unix()\n    return []byte(strconv.FormatInt(seconds, 10)), nil\n}\n<\/code><\/pre>\n
\u5e8f\u5217\u5316\u7684\u65f6\u5019\u4f1a\u8c03\u7528 MarshalJSON<\/p>\n
type TestObject struct {\n    Field timeImplementedMarshaler\n}\nshould := require.New(t)\nval := timeImplementedMarshaler(time.Unix(123, 0))\nobj := TestObject{val}\nbytes, err := jsoniter.Marshal(obj)\nshould.Nil(err)\nshould.Equal(`{\"Field\":123}`, string(bytes))\n<\/code><\/pre>\n
\u4f7f\u7528 RegisterTypeEncoder\u652f\u6301time.Time<\/h3>\n
jsoniter \u80fd\u591f\u5bf9\u4e0d\u662f\u4f60\u5b9a\u4e49\u7684type\u81ea\u5b9a\u4e49JSON\u7f16\u89e3\u7801\u65b9\u5f0f\u3002\u6bd4\u5982\u5bf9\u4e8e time.Time<\/code> \u53ef\u4ee5\u7528 epoch int64 \u6765\u5e8f\u5217\u5316<\/p>\n
import \"github.com\/json-iterator\/go\/extra\"\n\nextra.RegisterTimeAsInt64Codec(time.Microsecond)\noutput, err := jsoniter.Marshal(time.Unix(1, 1002))\nshould.Equal(\"1000001\", string(output))\n<\/code><\/pre>\n
\u5982\u679c\u8981\u81ea\u5b9a\u4e49\u7684\u8bdd\uff0c\u53c2\u89c1 RegisterTimeAsInt64Codec<\/code> \u7684\u5b9e\u73b0\u4ee3\u7801<\/p>\n
\u4f7f\u7528 MarshalText\u652f\u6301\u975e\u5b57\u7b26\u4e32\u4f5c\u4e3akey\u7684map<\/h3>\n
\u867d\u7136 JSON \u6807\u51c6\u91cc\u53ea\u652f\u6301 string<\/code> \u4f5c\u4e3a key<\/code> \u7684 map<\/code>\u3002\u4f46\u662f golang \u901a\u8fc7 MarshalText()<\/code> \u63a5\u53e3\uff0c\u4f7f\u5f97\u5176\u4ed6\u7c7b\u578b\u4e5f\u53ef\u4ee5\u4f5c\u4e3a map<\/code> \u7684 key<\/code>\u3002\u4f8b\u5982<\/p>\n
f, _, _ := big.ParseFloat(\"1\", 10, 64, big.ToZero)\nval := map[*big.Float]string{f: \"2\"}\nstr, err := MarshalToString(val)\nshould.Equal(`{\"1\":\"2\"}`, str)\n<\/code><\/pre>\n
\u5176\u4e2d big.Float<\/code> \u5c31\u5b9e\u73b0\u4e86 MarshalText()<\/code><\/p>\n
\u4f7f\u7528 json.RawMessage<\/h3>\n
\u5982\u679c\u90e8\u5206json\u6587\u6863\u6ca1\u6709\u6807\u51c6\u683c\u5f0f\uff0c\u6211\u4eec\u53ef\u4ee5\u628a\u539f\u59cb\u7684\u4fe1\u606f\u7528[]byte<\/code>\u4fdd\u5b58\u4e0b\u6765\u3002<\/p>\n
type TestObject struct {\n    Field1 string\n    Field2 json.RawMessage\n}\nvar data TestObject\njson.Unmarshal([]byte(`{\"field1\": \"hello\", \"field2\": [1,2,3]}`), &data)\nshould.Equal(` [1,2,3]`, string(data.Field2))\n<\/code><\/pre>\n
\u4f7f\u7528 json.Number<\/h3>\n
\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u5982\u679c\u662f interface{}<\/code> \u5bf9\u5e94\u6570\u5b57\u7684\u60c5\u51b5\u4f1a\u662f float64<\/code> \u7c7b\u578b\u7684\u3002\u5982\u679c\u8f93\u5165\u7684\u6570\u5b57\u6bd4\u8f83\u5927\uff0c\u8fd9\u4e2a\u8868\u793a\u4f1a\u6709\u635f\u7cbe\u5ea6\u3002\u6240\u4ee5\u53ef\u4ee5 UseNumber()<\/code> \u542f\u7528 json.Number<\/code> \u6765\u7528\u5b57\u7b26\u4e32\u8868\u793a\u6570\u5b57\u3002<\/p>\n
decoder1 := json.NewDecoder(bytes.NewBufferString(`123`))\ndecoder1.UseNumber()\nvar obj1 interface{}\ndecoder1.Decode(&obj1)\nshould.Equal(json.Number(\"123\"), obj1)\n<\/code><\/pre>\n
jsoniter \u652f\u6301\u6807\u51c6\u5e93\u7684\u8fd9\u4e2a\u7528\u6cd5\u3002\u540c\u65f6\uff0c\u6269\u5c55\u4e86\u884c\u4e3a\u4f7f\u5f97 Unmarshal<\/code> \u4e5f\u53ef\u4ee5\u652f\u6301 UseNumber<\/code> \u4e86\u3002<\/p>\n
json := Config{UseNumber:true}.Froze()\nvar obj interface{}\njson.UnmarshalFromString(\"123\", &obj)\nshould.Equal(json.Number(\"123\"), obj)\n<\/code><\/pre>\n
\u7edf\u4e00\u66f4\u6539\u5b57\u6bb5\u7684\u547d\u540d\u98ce\u683c<\/h3>\n
\u7ecf\u5e38 JSON \u91cc\u7684\u5b57\u6bb5\u540d Go \u91cc\u7684\u5b57\u6bb5\u540d\u662f\u4e0d\u4e00\u6837\u7684\u3002\u6211\u4eec\u53ef\u4ee5\u7528 field tag \u6765\u4fee\u6539\u3002<\/p>\n
output, err := jsoniter.Marshal(struct {\n    UserName      string `json:\"user_name\"`\n    FirstLanguage string `json:\"first_language\"`\n}{\n    UserName:      \"taowen\",\n    FirstLanguage: \"Chinese\",\n})\nshould.Equal(`{\"user_name\":\"taowen\",\"first_language\":\"Chinese\"}`, string(output))\n<\/code><\/pre>\n
\u4f46\u662f\u4e00\u4e2a\u4e2a\u5b57\u6bb5\u6765\u8bbe\u7f6e\uff0c\u592a\u9ebb\u70e6\u4e86\u3002\u5982\u679c\u4f7f\u7528 jsoniter\uff0c\u6211\u4eec\u53ef\u4ee5\u7edf\u4e00\u8bbe\u7f6e\u547d\u540d\u98ce\u683c\u3002<\/p>\n
import \"github.com\/json-iterator\/go\/extra\"\n\nextra.SetNamingStrategy(LowerCaseWithUnderscores)\noutput, err := jsoniter.Marshal(struct {\n    UserName      string\n    FirstLanguage string\n}{\n    UserName:      \"taowen\",\n    FirstLanguage: \"Chinese\",\n})\nshould.Nil(err)\nshould.Equal(`{\"user_name\":\"taowen\",\"first_language\":\"Chinese\"}`, string(output))\n<\/code><\/pre>\n
\u4f7f\u7528\u79c1\u6709\u7684\u5b57\u6bb5<\/h3>\n
Go \u7684\u6807\u51c6\u5e93\u53ea\u652f\u6301 public \u7684 field\u3002jsoniter \u989d\u5916\u652f\u6301\u4e86 private \u7684 field\u3002\u9700\u8981\u4f7f\u7528 SupportPrivateFields()<\/code> \u6765\u5f00\u542f\u5f00\u5173\u3002<\/p>\n
import \"github.com\/json-iterator\/go\/extra\"\n\nextra.SupportPrivateFields()\ntype TestObject struct {\n    field1 string\n}\nobj := TestObject{}\njsoniter.UnmarshalFromString(`{\"field1\":\"Hello\"}`, &obj)\nshould.Equal(\"Hello\", obj.field1)\n<\/code><\/pre>\n
\u5ffd\u7565\u6389\u4e00\u4e9b\u5b57\u6bb5<\/h3>\n
\u539f\u6587\u4e2d\u7b2c\u4e00\u8282\u6709\u4e2a\u9519\u8bef\uff0c\u6211\u66f4\u6b63\u8fc7\u6765\u4e86\u3002omitempty<\/code>\u4e0d\u4f1a\u5ffd\u7565\u67d0\u4e2a\u5b57\u6bb5\uff0c\u800c\u662f\u5ffd\u7565\u7a7a\u7684\u5b57\u6bb5\uff0c\u5f53\u5b57\u6bb5\u7684\u503c\u4e3a\u7a7a\u503c\u7684\u65f6\u5019\uff0c\u5b83\u4e0d\u4f1a\u51fa\u73b0\u5728JSON\u6570\u636e\u4e2d\u3002<\/p>\n
\u5982\u679c\u60f3\u5ffd\u7565\u67d0\u4e2a\u5b57\u6bb5\uff0c\u9700\u8981\u4f7f\u7528 json:\"-\"<\/code>\u683c\u5f0f\u3002<\/p>\n
type User struct {\n    Email    string `json:\"email\"`\n    Password string `json:\"password\"`\n    \/\/ many more fields\u2026\n}\n<\/code><\/pre>\n
\u5982\u679c\u60f3\u4e34\u65f6\u5ffd\u7565\u6389\u7a7aPassword<\/code>\u5b57\u6bb5,\u53ef\u4ee5\u7528-<\/code>:<\/p>\n
json.Marshal(struct {\n    *User\n    Password bool `json:\"-\"`\n}{\n    User: user,\n})\n<\/code><\/pre>\n
\u5ffd\u7565\u6389\u4e00\u4e9b\u5b57\u6bb52<\/h3>\n
\u5982\u679c\u4e0d\u60f3\u66f4\u6539\u539fstruct,\u8fd8\u53ef\u4ee5\u4f7f\u7528\u4e0b\u9762\u7684\u65b9\u6cd5\uff1a<\/p>\n
type User struct {\n    Email    string `json:\"email\"`\n    Password string `json:\"password\"`\n    \/\/ many more fields\u2026\n}\n\ntype omit *struct{}\n\ntype PublicUser struct {\n    *User\n    Password omit `json:\"-\"`\n}\n\njson.Marshal(PublicUser{\n    User: user,\n})\n<\/code><\/pre>\n
\u539f\u6587\uff1a<\/p>\n
    \n
  • https:\/\/colobu.com\/2017\/06\/21\/json-tricks-in-Go\/<\/li>\n
  • http:\/\/jsoniter.com\/go-tips.cn.html<\/li>\n
  • https:\/\/attilaolah.eu\/2014\/09\/10\/json-and-struct-composition-in-go\/<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"
    \u4e34\u65f6\u5ffd\u7565struct\u7a7a\u5b57\u6bb5 type User struct { Email string `json:”em […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[],"class_list":["post-7493","post","type-post","status-publish","format-standard","hentry","category-code_related"],"_links":{"self":[{"href":"https:\/\/kyle.ai\/blog\/wp-json\/wp\/v2\/posts\/7493","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/kyle.ai\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/kyle.ai\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/kyle.ai\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/kyle.ai\/blog\/wp-json\/wp\/v2\/comments?post=7493"}],"version-history":[{"count":2,"href":"https:\/\/kyle.ai\/blog\/wp-json\/wp\/v2\/posts\/7493\/revisions"}],"predecessor-version":[{"id":7495,"href":"https:\/\/kyle.ai\/blog\/wp-json\/wp\/v2\/posts\/7493\/revisions\/7495"}],"wp:attachment":[{"href":"https:\/\/kyle.ai\/blog\/wp-json\/wp\/v2\/media?parent=7493"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kyle.ai\/blog\/wp-json\/wp\/v2\/categories?post=7493"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kyle.ai\/blog\/wp-json\/wp\/v2\/tags?post=7493"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}