blocks|key|516389|text|要在对象上调用方法，首先使用reflect.ValueOf。然后按名称查找该方法，最后调用找到的方法。例如：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|516390|package+main

import+"fmt"
import+"reflect"

type+T+struct+{}

func+(t+*T)+Foo()+{
++++fmt.Println("foo")
}

func+main()+{
++++var+t+T
++++reflect.ValueOf(&t).MethodByName("Foo").Call([]reflect.Value{})
}|code-block|syntax|javascript|516391|entityMap^0|E|F|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

To call a method on an object, first use <code>reflect.ValueOf</code>. Then find the method by name, and then finally call the found method. For example:

<pre><code>package main

import "fmt"
import "reflect"

type T struct {}

func (t *T) Foo() {
 fmt.Println("foo")
}

func main() {
 var t T
 reflect.ValueOf(&amp;t).MethodByName("Foo").Call([]reflect.Value{})
}
</code></pre>

blocks|key|732900|text|具有错误处理功能的gist调用结构方法|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|732901|//+Invoke+-+firstResult,+err+:=+Invoke(AnyStructInterface,+MethodName,+Params...)
func+invoke(any+interface{},+name+string,+args+...interface{})+(reflect.Value,+error)+{
++++method+:=+reflect.ValueOf(any).MethodByName(name)
++++methodType+:=+method.Type()
++++numIn+:=+methodType.NumIn()
++++if+numIn+>+len(args)+{
++++++++return+reflect.ValueOf(nil),+fmt.Errorf("Method+%25s+must+have+minimum+%25d+params.+Have+%25d",+name,+numIn,+len(args))
++++}
++++if+numIn+!=+len(args)+&&+!methodType.IsVariadic()+{
++++++++return+reflect.ValueOf(nil),+fmt.Errorf("Method+%25s+must+have+%25d+params.+Have+%25d",+name,+numIn,+len(args))
++++}
++++in+:=+make([]reflect.Value,+len(args))
++++for+i+:=+0;+i+<+len(args);+i%2B%2B+{
++++++++var+inType+reflect.Type
++++++++if+methodType.IsVariadic()+&&+i+>=+numIn-1+{
++++++++++++inType+=+methodType.In(numIn+-+1).Elem()
++++++++}+else+{
++++++++++++inType+=+methodType.In(i)
++++++++}
++++++++argValue+:=+reflect.ValueOf(args[i])
++++++++if+!argValue.IsValid()+{
++++++++++++return+reflect.ValueOf(nil),+fmt.Errorf("Method+%25s.+Param[%25d]+must+be+%25s.+Have+%25s",+name,+i,+inType,+argValue.String())
++++++++}
++++++++argType+:=+argValue.Type()
++++++++if+argType.ConvertibleTo(inType)+{
++++++++++++in[i]+=+argValue.Convert(inType)
++++++++}+else+{
++++++++++++return+reflect.ValueOf(nil),+fmt.Errorf("Method+%25s.+Param[%25d]+must+be+%25s.+Have+%25s",+name,+i,+inType,+argType)
++++++++}
++++}
++++return+method.Call(in)[0],+nil
}|code-block|syntax|javascript|732902|entityMap|0|LINK|mutability|MUTABLE|url|https://gist.github.com/yaxinr/679976f1cde2a7b2925c30fa89b03eea^0|9|4|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@$A|R|B|S|1|T]]|C|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|C|$G|H]]|$1|I|3|-4|5|6|7|V|8|@]|9|@]|C|$]]]|J|$K|$5|L|M|N|C|$O|P]]]]

<a href="https://gist.github.com/yaxinr/679976f1cde2a7b2925c30fa89b03eea" rel="nofollow noreferrer">gist</a>
invoke struct method with error handling

<pre><code>// Invoke - firstResult, err := Invoke(AnyStructInterface, MethodName, Params...)
func invoke(any interface{}, name string, args ...interface{}) (reflect.Value, error) {
 method := reflect.ValueOf(any).MethodByName(name)
 methodType := method.Type()
 numIn := methodType.NumIn()
 if numIn &gt; len(args) {
 return reflect.ValueOf(nil), fmt.Errorf("Method %s must have minimum %d params. Have %d", name, numIn, len(args))
 }
 if numIn != len(args) &amp;&amp; !methodType.IsVariadic() {
 return reflect.ValueOf(nil), fmt.Errorf("Method %s must have %d params. Have %d", name, numIn, len(args))
 }
 in := make([]reflect.Value, len(args))
 for i := 0; i &lt; len(args); i++ {
 var inType reflect.Type
 if methodType.IsVariadic() &amp;&amp; i &gt;= numIn-1 {
 inType = methodType.In(numIn - 1).Elem()
 } else {
 inType = methodType.In(i)
 }
 argValue := reflect.ValueOf(args[i])
 if !argValue.IsValid() {
 return reflect.ValueOf(nil), fmt.Errorf("Method %s. Param[%d] must be %s. Have %s", name, i, inType, argValue.String())
 }
 argType := argValue.Type()
 if argType.ConvertibleTo(inType) {
 in[i] = argValue.Convert(inType)
 } else {
 return reflect.ValueOf(nil), fmt.Errorf("Method %s. Param[%d] must be %s. Have %s", name, i, inType, argType)
 }
 }
 return method.Call(in)[0], nil
}
</code></pre>

blocks|key|516460|text|package+main

import+(
++++"fmt"
++++"reflect"
)

type+Log+struct+{
++++Path++string
++++Level+string
}

func+(l+*Log)+Conversion(i+interface{})+{

++++if+data,+ok+:=+i.(*Log);+ok+{
++++++++if+data+!=+nil+{
++++++++++++if+len(data.Path)+>+0+{
++++++++++++++++l.Path+=+data.Path
++++++++++++}
++++++++++++if+len(data.Level)+>+0+{
++++++++++++++++l.Level+=+data.Level
++++++++++++}
++++++++}
++++}
}

type+Storage+struct+{
++++Type+++++++string
++++ServerList+[]string
}

func+(s+*Storage)+Conversion(i+interface{})+{

+++if+data,+ok+:=+i.(*Storage);+ok+{
++++++++if+data+!=+nil+{
++++++++++++if+len(data.Type)+>+0+{
++++++++++++++++s.Type+=+data.Type
++++++++++++}
++++++++}
++++}
}

type+Server+struct+{
++++LogConfig+++++*Log
++++StorageConfig+*Storage
}

func+main()+{
++++def+:=+Server{
++++++++LogConfig:+&Log{
++++++++++++Path:++"/your/old/log/path/",
++++++++++++Level:+"info",
++++++++},
++++++++StorageConfig:+&Storage{
++++++++++++Type:+++++++"zookeeper",
++++++++++++ServerList:+[]string{"127.0.0.1:2181"},
++++++++},
++++}

++++fmt.Println(def)
++++cur+:=+Server{
++++++++LogConfig:+&Log{
++++++++++++Path:++"/your/new/log/path/",
++++++++++++Level:+"debug",
++++++++},
++++++++StorageConfig:+&Storage{
++++++++++++Type:+++++++"etcd",
++++++++++++ServerList:+[]string{"127.0.0.1:2379"},
++++++++},
++++}

++++fmt.Println(cur)

++++defV+:=+reflect.ValueOf(def)
++++curV+:=+reflect.ValueOf(cur)
++++for+k+:=+0;+k+<+defV.NumField();+k%2B%2B+{
++++++++in+:=+make([]reflect.Value,+1)
++++++++in[0]+=+reflect.ValueOf(curV.Field(k).Interface())
++++++++defV.Field(k).MethodByName("Conversion").Call(in)
++++}

++++fmt.Println(def.LogConfig)
++++fmt.Println(def.StorageConfig)
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|516461|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>package main

import (
 "fmt"
 "reflect"
)

type Log struct {
 Path string
 Level string
}

func (l *Log) Conversion(i interface{}) {

 if data, ok := i.(*Log); ok {
 if data != nil {
 if len(data.Path) &gt; 0 {
 l.Path = data.Path
 }
 if len(data.Level) &gt; 0 {
 l.Level = data.Level
 }
 }
 }
}

type Storage struct {
 Type string
 ServerList []string
}

func (s *Storage) Conversion(i interface{}) {

 if data, ok := i.(*Storage); ok {
 if data != nil {
 if len(data.Type) &gt; 0 {
 s.Type = data.Type
 }
 }
 }
}

type Server struct {
 LogConfig *Log
 StorageConfig *Storage
}

func main() {
 def := Server{
 LogConfig: &amp;Log{
 Path: "/your/old/log/path/",
 Level: "info",
 },
 StorageConfig: &amp;Storage{
 Type: "zookeeper",
 ServerList: []string{"127.0.0.1:2181"},
 },
 }

 fmt.Println(def)
 cur := Server{
 LogConfig: &amp;Log{
 Path: "/your/new/log/path/",
 Level: "debug",
 },
 StorageConfig: &amp;Storage{
 Type: "etcd",
 ServerList: []string{"127.0.0.1:2379"},
 },
 }

 fmt.Println(cur)

 defV := reflect.ValueOf(def)
 curV := reflect.ValueOf(cur)
 for k := 0; k &lt; defV.NumField(); k++ {
 in := make([]reflect.Value, 1)
 in[0] = reflect.ValueOf(curV.Field(k).Interface())
 defV.Field(k).MethodByName("Conversion").Call(in)
 }

 fmt.Println(def.LogConfig)
 fmt.Println(def.StorageConfig)
}
</code></pre>

I have found a function call <code>MethodByName()</code> here <a href="http://golang.org/pkg/reflect/#Value.MethodByName" rel="noreferrer">http://golang.org/pkg/reflect/#Value.MethodByName</a> but it's not exactly what I want! (maybe because I don't know how to use it ... I cannot find any example with it). What I want is:

<pre><code>type MyStruct struct {
//some feilds here
} 
func (p *MyStruct) MyMethod { 
 println("My statement."); 
} 

CallFunc("MyStruct", "MyMethod"); 
//print out "My statement." 
</code></pre>

So I guess, first I need something like <code>StructByName()</code> and after that use it for <code>MethodByName()</code>, is that right!?

Call a Struct and its Method by name in Go?

我在这里找到了一个名为MethodByName()的函数，但它并不是我想要的！(也许是因为我不知道如何使用它。我找不到任何使用它的例子)。我想要的是：type MyStruct struct {//some feilds here} func (p *MyStruct) MyMethod {     println("...

问在Go中按名称调用Struct及其方法？
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