{"id":192395,"date":"2020-11-08T19:43:50","date_gmt":"2020-11-08T11:43:50","guid":{"rendered":"http:\/\/4563.org\/?p=192395"},"modified":"2020-11-08T19:43:50","modified_gmt":"2020-11-08T11:43:50","slug":"%e8%af%b7%e6%95%99%e4%b8%80%e4%b8%aa-golang-%e4%b8%ad-reflect-%e7%9a%84%e9%97%ae%e9%a2%98-%e7%90%a2%e7%a3%a8%e4%ba%86%e4%b8%80%e4%b8%8b%e5%8d%88%e4%ba%86","status":"publish","type":"post","link":"http:\/\/4563.org\/?p=192395","title":{"rendered":"\u8bf7\u6559\u4e00\u4e2a golang \u4e2d reflect \u7684\u95ee\u9898, \u7422\u78e8\u4e86\u4e00\u4e0b\u5348\u4e86"},"content":{"rendered":"
\n
\n
\n

\u8bf7\u6559\u4e00\u4e2a golang \u4e2d reflect \u7684\u95ee\u9898, \u7422\u78e8\u4e86\u4e00\u4e0b\u5348\u4e86 <\/h1>\n

<\/p>\n

\n
\u8cc7\u6df1\u5927\u4f6c : Vibra <\/span> <\/i> 8<\/span> <\/div>\n
<\/div>\n<\/p><\/div>\n<\/p><\/div>\n<\/p><\/div>\n
<\/p>\n
package main  import (     \"fmt\"     \"reflect\" )  type arrT struct {     Arr []int }   func main() {  tt := arrT{   Arr: []int{1, 2},  }   arrValue := reflect.ValueOf(&tt).Elem().FieldByName(\"Arr\")  fmt.Printf(\"%v, %Tn\", arrValue, arrValue)   aValue := arrValue.Elem()  aValue.Set(reflect.Append(aValue, reflect.ValueOf(80)))  \/\/ panic: reflect: call of reflect.Value.Elem on slice Value      fmt.Println(\"Slice after appending data:\", tt) } <\/code><\/pre>\n
\u5982\u4ee3\u7801\u6240\u793a<\/p>\n
\u4e00\u4e2a\u7ed3\u6784\u4f53\u4e2d\u6709\u4e00\u4e2a split \u6211\u60f3\u5728\u91cc\u9762\u6dfb\u52a0\u4e00\u4e9b\u4e1c\u897f, \u4f46\u662f\u4e00\u76f4\u62a5\u9519, \u600e\u6837\u624d\u80fd\u987a\u5229\u6dfb\u52a0\u8fdb\u53bb\u5462?<\/p>\n<\/p><\/div>\n
 \u5927\u4f6c\u6709\u8a71\u8aaa<\/b> (21<\/span>)        <\/div>\n
 <\/div>\n<\/p><\/div>\n<\/p><\/div>\n
    \n
  • \n
    \n
    \n
     \u8cc7\u6df1\u5927\u4f6c : emeab <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 \u62a5\u5565\u9519\u554a                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
     \u4e3b<\/span> \u8cc7\u6df1\u5927\u4f6c : Vibra <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 @emeab \u9519\u8bef\u5199\u5728\u4e86\u4ee3\u7801\u4e2d\u4e86 `panic: reflect: call of reflect.Value.Elem on slice Value`                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
     \u8cc7\u6df1\u5927\u4f6c : impl <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 Go \u5723\u7ecf\u6ca1\u770b\u8fc7\uff1f\u5c11\u7528 reflect \u548c unsafe \u8fd9\u4e24\u4e2a\u5305                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
     \u8cc7\u6df1\u5927\u4f6c : suke971219 <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 \u4f7f\u7528 .([]int) \u63a8\u7b97\u7c7b\u578b\uff0c\u4fee\u6539\u5207\u7247\u8bd5\u8bd5\u5427                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
     \u4e3b<\/span> \u8cc7\u6df1\u5927\u4f6c : Vibra <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 @impl \u4e3b\u8981\u662f\u81ea\u5df1\u5bf9 golang \u4e0d\u662f\u5f88\u719f\u6089,\u4e00\u719f\u6089\u4e00\u4e0b\u8bed\u6cd5, \u4e8c\u662f\u6709\u70b9\u4ee3\u7801\u6d01\u7656\u5427 reflect \u8282\u7701\u4e86\u5927\u91cf\u7684\u91cd\u590d\u4ee3\u7801                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
     \u4e3b<\/span> \u8cc7\u6df1\u5927\u4f6c : Vibra <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 @suke971219 \u8fd9\u4e2a\u4fee\u6539\u4e0d\u5230\u539f\u672c\u7684\u5207\u7247\u5440, \u6211\u73b0\u5728\u5df2\u7ecf\u4fee\u6539\u597d\u4e86, \u8c22\u8c22. \u4ee3\u7801\u9644\u4e0a\u4f9b\u5927\u5bb6\u53c2\u8003
    “`golang<\/p>\n
    func main() {
     tt := arrT{
     Arr: []int{1, 2},
     }<\/p>\n
     arrValue := reflect.ValueOf(&tt).Elem().FieldByName(“Arr”)
     fmt.Printf(“%v, %Tn”, arrValue, arrValue)<\/p>\n
     arrValue.Set(reflect.Append(arrValue, reflect.ValueOf(80)))<\/p>\n
     fmt.Println(“Slice after appending data:”, tt.Arr)
    }
    “`                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
     \u8cc7\u6df1\u5927\u4f6c : mason961125 <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 \u5efa\u8bae\u9605\u8bfb https:\/\/blog.golang.org\/laws-of-reflection                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
     \u8cc7\u6df1\u5927\u4f6c : merin96 <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 \u8fd9\u73a9\u610f\u6162\u5f97\u5f88\uff0c\u5c0f\u5fc3\u4f7f\u7528                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
     \u8cc7\u6df1\u5927\u4f6c : BBCCBB <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 \u8fd9\u62a5\u9519\u5e94\u8be5\u662f aValue := arrValue.Elem() \u8fd9\u4e00\u884c\u7684\u6570\u636e, <\/p>\n
    arrValue := reflect.ValueOf(&tt).Elem().FieldByName(“Arr”) \u4f60\u5728\u8fd9\u91cc\u5df2\u7ecf\u8c03\u7528\u8fc7 Elem()\u4e86, \u83b7\u53d6\u5230\u7684\u5c31\u662f slice \u4e86, slice \u6ca1\u6cd5\u518d elem()\u4e86.                                                            <\/p><\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
     \u8cc7\u6df1\u5927\u4f6c : CEBBCAT <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 @impl \u5c11\u7528\u53c8\u4e0d\u662f\u4e0d\u80fd\u7528\uff0c\u73b0\u5728\u5c31\u662f\u8981\u89e3\u51b3\u7528\u5f97\u4e0d\u597d\u7684\u95ee\u9898\u3002\u5c31\u50cf\u4eba\u5bb6\u5728\u5c1d\u8bd5\u4f7f\u7528 goto \u89e3\u51b3\u8df3\u51fa\u5faa\u73af\u7684\u95ee\u9898\u65f6\uff0c\u65c1\u4eba\u63d2\u4e00\u5634 goto \u662f\u6bd2\u836f\uff0c\u4e0d\u80fd\u7528\uff0c\u8fd9\u4e0d\u662f\u641e\u7b11\u5462\u5417\uff1f                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
     \u8cc7\u6df1\u5927\u4f6c : useben <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 \u4e00\u5806\u4eba\u90fd\u4e0d\u77e5\u9053\u8bf4\u4ec0\u4e48…<\/p>\n
    reflect.ValueOf(&tt).Elem() \u8fd9\u91cc\u5df2\u7ecf\u5bf9\u5bf9\u8c61\u6307\u9488\u76f8\u5f53\u4e8e\u89e3\u5f15\u7528\u4e86, \u5df2\u7ecf\u62ff\u5230\u5bf9\u8c61\u503c\u4fe1\u606f, aValue := arrValue.Elem() \u8fd9\u91cc\u6ca1\u5fc5\u8981\u518d\u7528 Elem() , \u4fee\u6539\u4e3a\u4e00\u4e0b\u5373\u53ef<\/p>\n
    “`go
    package main<\/p>\n
    import (
     “fmt”
     “reflect”
    )<\/p>\n
    type arrT struct {
     Arr []int
    }<\/p>\n
    func main() {
     tt := arrT{
     Arr: []int{1, 2},
     }<\/p>\n
     arrValue := reflect.ValueOf(&tt).Elem().FieldByName(“Arr”)
     fmt.Printf(“%v, %Tn”, arrValue, arrValue)<\/p>\n
     aValue := arrValue
     aValue.Set(reflect.Append(aValue, reflect.ValueOf(80)))<\/p>\n
     fmt.Println(“Slice after appending data:”, tt)
    }
    “`                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
     \u8cc7\u6df1\u5927\u4f6c : GopherDaily <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 @Vibra \u5bf9                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
     \u8cc7\u6df1\u5927\u4f6c : impl <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 @CEBBCAT \u6211\u8bf4\u4e0d\u80fd\u7528\u4e86\u5417\uff1f\u8981\u4e0d\u56de\u53bb\u5b66\u6821\u627e\u4f53\u80b2\u8001\u5e08\u6559\u4f60\u8bed\u6587\uff1f                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
     \u8cc7\u6df1\u5927\u4f6c : dimlau <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 @impl <\/p>\n
    1 \u3001\u9876\u4f5c\u8005\u6ca1\u8bf4\u8981\u591a\u7528 reflect \u548c unsafe \u8fd9\u4e24\u4e2a\u5305\uff0c\u53ea\u662f\u5728\u4f7f\u7528\u65f6\u9047\u5230\u4e86\u5177\u4f53\u95ee\u9898\u5e0c\u671b\u63a2\u8ba8\u3002
    —> \u800c\u59b3\u56de\u590d\u8bf4 Go \u5723\u7ecf\u4e3b\u5f20\u5c11\u7528\uff1b<\/p>\n
    2 \u3001 @CEBBCAT \u53cd\u9a73\u59b3\u8bf4\u300c\u5c11\u7528\u53c8\u4e0d\u662f\u4e0d\u80fd\u7528\u300d\uff0c\u610f\u601d\u662f\u4f1a\u5c3d\u91cf\u5c11\u7528\u4f46\u662f\u5728\u7528\u7684\u65f6\u5019\u9047\u5230\u95ee\u9898\u8fd8\u662f\u8981\u89e3\u51b3\u554a\u3002
    —> \u800c\u59b3\u56de\u590d\u8bf4\u300c\u6211\u8bf4\u4e0d\u80fd\u7528\u4e86\u5417\uff1f\u300d\u3002<\/p>\n
    \u4f3c\u4e4e\u8fd9\u4e24\u6b21\u4e92\u52a8\u90fd\u662f\u59b3\uff08\u4e0d\u77e5\u662f\u5426\u6545\u610f\u5730\uff09\u7406\u89e3\u9519\u4e86\u522b\u4eba\u7684\u610f\u601d\uff0c\u4e3a\u4ec0\u4e48\u8fd8\u8981\u8ba9\u522b\u4eba\u56de\u5b66\u6821\u5b66\u8bed\u6587\u5462\uff1f                                                            <\/p><\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
     \u8cc7\u6df1\u5927\u4f6c : impl <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 @dimlau \u770b\u770b\u4ed6\u4e3e\u7684 goto \u4f8b\u5b50                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
     \u8cc7\u6df1\u5927\u4f6c : no1xsyzy <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 @impl \u90a3\u6211\u95ee\u4f60\uff1a\u4f60\u5728 #3 \u8bf4\u5c11\u7528\u7684\u76ee\u7684\u662f\u4ec0\u4e48\uff1f\u5bf9\u4e3b\u7684\u95ee\u9898\u6709\u4f55\u5efa\u6811\uff1f
    \u731c\u60f3\u7684\u53ef\u80fd\uff1a
    1. \u4f60\u8ba4\u4e3a\u8fd9\u4e2a\u95ee\u9898\u53ef\u4ee5\u66f4\u4f18\u96c5\u5730\u5b9e\u73b0\uff0c\u4e0d\u9700\u8981 reflect\uff0c\u90a3\u4f60 #13 \u7684\u56de\u590d\u5c31\u663e\u5f97\u975e\u5e38\u8be1\u5f02\u3002
    2. \u4f60\u8bf4\u7684\u8bdd\u4e0e\u4e3b\u9898\u6839\u672c\u65e0\u5173<\/p>\n
    \u4f60\u8981\u7ea0\u7ed3\u81ea\u53e5\uff0c\u90a3 #10 \u628a \u201c\u4e0d\u80fd\u7528\u201d \u6539\u6210 \u201c\u5c11\u7528\u201d \u4e0d\u662f\u4e00\u6837\u7684\u5417\uff1f
    \u90a3\u54b1\u91cd\u65b0\u518d\u6765\u4e00\u904d\uff1f<\/p>\n
    \u5c11\u7528\u53c8\u4e0d\u662f\u4e0d\u80fd\u7528\uff0c\u73b0\u5728\u5c31\u662f\u8981\u89e3\u51b3\u7528\u5f97\u4e0d\u597d\u7684\u95ee\u9898\u3002\u5c31\u50cf\u4eba\u5bb6\u5728\u5c1d\u8bd5\u4f7f\u7528 goto \u89e3\u51b3\u8df3\u51fa\u5faa\u73af\u7684\u95ee\u9898\u65f6\uff0c\u65c1\u4eba\u63d2\u4e00\u5634 goto \u662f\u6bd2\u836f\uff0c\u5c11\u7528\uff0c\u8fd9\u4e0d\u662f\u641e\u7b11\u5462\u5417\uff1f                                                            <\/p><\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
     \u8cc7\u6df1\u5927\u4f6c : no1xsyzy <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 @no1xsyzy \u81ea\u53e5 -> \u5b57\u53e5                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
     \u8cc7\u6df1\u5927\u4f6c : impl <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 @no1xsyzy \u90a3\u4f60\u7684\u5efa\u8bae\u5c31\u662f\u4e00\u4e2a go \u521d\u5b66\u8005\u6d6a\u8d39\u4e00\u4e2a\u4e0b\u5348\u65f6\u95f4\u7422\u78e8\u600e\u4e48\u7528 reflect \u8fd9\u4e2a\u5305\u54af\uff1f                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
     \u8cc7\u6df1\u5927\u4f6c : lxz6597863 <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 “`go
    package main<\/p>\n
    import (
     “fmt”
     “reflect”
    )<\/p>\n
    type arrT struct {
     Arr []int
    }<\/p>\n
    func main() {
     tt := arrT{
     Arr: []int{1, 2},
     }<\/p>\n
     arrValue := reflect.ValueOf(&tt).Elem().FieldByName(“Arr”)
     fmt.Printf(“%v, %Tn”, arrValue, arrValue)<\/p>\n
     arrValue.Set(reflect.Append(arrValue, reflect.ValueOf(80)))
     \/\/ panic: reflect: call of reflect.Value.Elem on slice Value<\/p>\n
     fmt.Println(“Slice after appending data:”, tt)
    }
    “`                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
     \u8cc7\u6df1\u5927\u4f6c : 2435043xia <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 \u4e0a\u6b63\u89e3                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n
    \n
    \n
     \u8cc7\u6df1\u5927\u4f6c : no1xsyzy <\/span>  <\/div>\n
     <\/i>            <\/span> <\/div>\n<\/p><\/div>\n
                                                                 @impl \u6211\u611f\u89c9\u4f60\u7eaf\u7cb9\u662f\u4e0d\u4f1a\u8bf4\u8bdd\uff0c\u6216\u8005\u5fc3\u6001\u5d29\u4e86
    \u201c\u6211\u5efa\u8bae\u5148\u8003\u8651\u4e0d\u7528 reflect \u89e3\u51b3\u95ee\u9898\u3002\u53e6\u5916\uff0c\u4e3b\u53ef\u4ee5\u628a\u539f\u672c\u7684\u95ee\u9898\u95ee\u51fa\u6765\uff0c\u4ee5\u907f\u514d\u8fd9\u662f\u4e2a\u6f5c\u5728\u7684 X-Y \u95ee\u9898\u201d
    \u8fd9\u662f\u5426\u6b63\u786e\u8868\u8fbe\u4e86\u4f60\u7684\u610f\u56fe\uff1f\u540c\u65f6\uff0c\u8fd9\u6837\u4e00\u6bb5\u8bdd\u53c8\u80fd\u663e\u5f97\u8bf4\u8bdd\u4eba\u6e29\u548c\u8c26\u865a\u4e14\u535a\u5b66\u3002                                                            <\/div>\n<\/p><\/div>\n<\/li>\n
  • \n","protected":false},"excerpt":{"rendered":"
    \u8bf7\u6559\u4e00\u4e2a golang \u4e2d ref…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[],"tags":[],"_links":{"self":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts\/192395"}],"collection":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=192395"}],"version-history":[{"count":0,"href":"http:\/\/4563.org\/index.php?rest_route=\/wp\/v2\/posts\/192395\/revisions"}],"wp:attachment":[{"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=192395"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=192395"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/4563.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=192395"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}