blocks|key|96836|text|我想推荐go-spew，根据他们的github的说法，它“为Go数据结构实现了一个非常漂亮的深度打印机，以帮助调试”。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|96837|go+get+-u+github.com/davecgh/go-spew/spew|code-block|syntax|javascript|96838|使用示例：|96839|package+main

import+(
++++"github.com/davecgh/go-spew/spew"
)

type+Project+struct+{
++++Id++++++int64++`json:"project_id"`
++++Title+++string+`json:"title"`
++++Name++++string+`json:"name"`
++++Data++++string+`json:"data"`
++++Commits+string+`json:"commits"`
}

func+main()+{

++++o+:=+Project{Name:+"hello",+Title:+"world"}
++++spew.Dump(o)
}|96840|输出：|96841|(main.Project)+{
+Id:+(int64)+0,
+Title:+(string)+(len=5)+"world",
+Name:+(string)+(len=5)+"hello",
+Data:+(string)+"",
+Commits:+(string)+""
}|96842|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/davecgh/go-spew^0|4|7|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@$A|Z|B|10|1|11]]|C|$]]|$1|D|3|E|5|F|7|12|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|13|8|@]|9|@]|C|$]]|$1|K|3|L|5|F|7|14|8|@]|9|@]|C|$G|H]]|$1|M|3|N|5|6|7|15|8|@]|9|@]|C|$]]|$1|O|3|P|5|F|7|16|8|@]|9|@]|C|$G|H]]|$1|Q|3|-4|5|6|7|17|8|@]|9|@]|C|$]]]|R|$S|$5|T|U|V|C|$W|X]]]]

I want to recommend <a href="https://github.com/davecgh/go-spew">go-spew</a>, which according to their github "Implements a deep pretty printer for Go data structures to aid in debugging"

<pre><code>go get -u github.com/davecgh/go-spew/spew
</code></pre>

usage example:

<pre><code>package main

import (
 "github.com/davecgh/go-spew/spew"
)

type Project struct {
 Id int64 `json:"project_id"`
 Title string `json:"title"`
 Name string `json:"name"`
 Data string `json:"data"`
 Commits string `json:"commits"`
}

func main() {

 o := Project{Name: "hello", Title: "world"}
 spew.Dump(o)
}
</code></pre>

output:

<pre><code>(main.Project) {
 Id: (int64) 0,
 Title: (string) (len=5) "world",
 Name: (string) (len=5) "hello",
 Data: (string) "",
 Commits: (string) ""
}
</code></pre>

blocks|key|96875|text|还有go-render，它为字符串和整数映射处理指针递归和大量的键排序。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|96876|安装：|96877|go+get+github.com/luci/go-render/render|code-block|syntax|javascript|96878|示例：|96879|type+customType+int
type+testStruct+struct+{
++++++++S+string
++++++++V+*map[string]int
++++++++I+interface{}
}

a+:=+testStruct{
++++++++S:+"hello",
++++++++V:+&map[string]int{"foo":+0,+"bar":+1},
++++++++I:+customType(42),
}

fmt.Println("Render+test:")
fmt.Printf("fmt.Printf:++++%25#v\n",+a)))
fmt.Printf("render.Render:+%25s\n",+Render(a))|96880|打印的内容：|96881|fmt.Printf:++++render.testStruct{S:"hello",+V:(*map[string]int)(0x600dd065),+I:42}
render.Render:+render.testStruct{S:"hello",+V:(*map[string]int){"bar":1,+"foo":0},+I:render.customType(42)}|96882|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/luci/go-render^0|2|9|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|10|8|@]|9|@$A|11|B|12|1|13]]|C|$]]|$1|D|3|E|5|6|7|14|8|@]|9|@]|C|$]]|$1|F|3|G|5|H|7|15|8|@]|9|@]|C|$I|J]]|$1|K|3|L|5|6|7|16|8|@]|9|@]|C|$]]|$1|M|3|N|5|H|7|17|8|@]|9|@]|C|$I|J]]|$1|O|3|P|5|6|7|18|8|@]|9|@]|C|$]]|$1|Q|3|R|5|H|7|19|8|@]|9|@]|C|$I|J]]|$1|S|3|-4|5|6|7|1A|8|@]|9|@]|C|$]]]|T|$U|$5|V|W|X|C|$Y|Z]]]]

There's also <a href="https://github.com/luci/go-render" rel="nofollow">go-render</a>, which handles pointer recursion and lots of key sorting for string and int maps. 

Installation:

<pre><code>go get github.com/luci/go-render/render
</code></pre>

Example:

<pre><code>type customType int
type testStruct struct {
 S string
 V *map[string]int
 I interface{}
}

a := testStruct{
 S: "hello",
 V: &amp;map[string]int{"foo": 0, "bar": 1},
 I: customType(42),
}

fmt.Println("Render test:")
fmt.Printf("fmt.Printf: %#v\n", a)))
fmt.Printf("render.Render: %s\n", Render(a))
</code></pre>

Which prints:

<pre><code>fmt.Printf: render.testStruct{S:"hello", V:(*map[string]int)(0x600dd065), I:42}
render.Render: render.testStruct{S:"hello", V:(*map[string]int){"bar":1, "foo":0}, I:render.customType(42)}
</code></pre>

blocks|key|96917|text|访问here查看完整的代码。在这里，您还可以找到一个在线终端的链接，在那里可以运行完整的代码，程序表示如何提取结构的信息(字段的名称、类型和值)。下面是仅打印字段名称的程序片段。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|96918|package+main

import+"fmt"
import+"reflect"

func+main()+{
++++type+Book+struct+{
++++++++Id++++int
++++++++Name++string
++++++++Title+string
++++}

++++book+:=+Book{1,+"Let+us+C",+"Enjoy+programming+with+practice"}
++++e+:=+reflect.ValueOf(&book).Elem()

++++for+i+:=+0;+i+<+e.NumField();+i%2B%2B+{
++++++++fieldName+:=+e.Type().Field(i).Name
++++++++fmt.Printf("%25v\n",+fieldName)
++++}
}

/*
Id
Name
Title
*/|code-block|syntax|javascript|96919|entityMap|0|LINK|mutability|MUTABLE|url|https://gist.github.com/hygull/0fbc428dc77bef4a665b19d598f865d8^0|2|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]]]]

Visit <a href="https://gist.github.com/hygull/0fbc428dc77bef4a665b19d598f865d8" rel="nofollow noreferrer">here</a> to see the complete code. Here you will also find a link for an online terminal where the complete code can be run and the program represents how to extract structure's information(field's name their type &amp; value). Below is the program snippet that only prints the field names.

<pre><code>package main

import "fmt"
import "reflect"

func main() {
 type Book struct {
 Id int
 Name string
 Title string
 }

 book := Book{1, "Let us C", "Enjoy programming with practice"}
 e := reflect.ValueOf(&amp;book).Elem()

 for i := 0; i &lt; e.NumField(); i++ {
 fieldName := e.Type().Field(i).Name
 fmt.Printf("%v\n", fieldName)
 }
}

/*
Id
Name
Title
*/
</code></pre>

blocks|key|4603149|text|如果您想要struct的某种格式化输出，我认为实现自定义字符串会更好|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|4603150|例如|4603151|package+main

++++import+"fmt"

++++type+Project+struct+{
++++++++Id+int64+`json:"project_id"`
++++++++Title+string+`json:"title"`
++++++++Name+string+`json:"name"`
++++}

++++func+(p+Project)+String()+string+{
++++++++return+fmt.Sprintf("{Id:%25d,+Title:%25s,+Name:%25s}",+p.Id,+p.Title,+p.Name)
++++}

++++func+main()+{
++++++++o+:=+Project{Id:+4,+Name:+"hello",+Title:+"world"}
++++++++fmt.Printf("%25%2Bv\n",+o)
++++}|code-block|syntax|javascript|4603152|entityMap^0|5|6|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|R|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|S|8|@]|D|@]|E|$K|L]]|$1|M|3|-4|5|6|7|T|8|@]|D|@]|E|$]]]|N|$]]

I think it would be better to implement a custom stringer if you want some kind of formatted output of a <code>struct</code>
for example
<pre><code>package main

 import &quot;fmt&quot;

 type Project struct {
 Id int64 `json:&quot;project_id&quot;`
 Title string `json:&quot;title&quot;`
 Name string `json:&quot;name&quot;`
 }

 func (p Project) String() string {
 return fmt.Sprintf(&quot;{Id:%d, Title:%s, Name:%s}&quot;, p.Id, p.Title, p.Name)
 }

 func main() {
 o := Project{Id: 4, Name: &quot;hello&quot;, Title: &quot;world&quot;}
 fmt.Printf(&quot;%+v\n&quot;, o)
 }
</code></pre>

blocks|key|96998|text|另一种方法是，创建一个名为toString的函数，它接受结构，根据需要格式化字段。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|96999|import+(
++++"fmt"
)

type+T+struct+{
++++x,+y+string
}

func+(r+T)+toString()+string+{
++++return+"Formate+as+u+need+:"+%2B+r.x+%2B+r.y
}

func+main()+{
++++r1+:=+T{"csa",+"ac"}
++++fmt.Println("toStringed+:+",+r1.toString())
}|code-block|syntax|javascript|97000|entityMap^0|D|8|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|$]]

Another way is, create a func called <code>toString</code> that takes struct, format the
fields as you wish.

<pre><code>import (
 "fmt"
)

type T struct {
 x, y string
}

func (r T) toString() string {
 return "Formate as u need :" + r.x + r.y
}

func main() {
 r1 := T{"csa", "ac"}
 fmt.Println("toStringed : ", r1.toString())
}
</code></pre>

blocks|key|97004|text|p+=+Project{...}
fmt.Printf("%25%2Bv",+p)
fmt.Printf("%25#v",+p)+//with+type|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|97005|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>p = Project{...}
fmt.Printf("%+v", p)
fmt.Printf("%#v", p) //with type
</code></pre>

blocks|key|4603291|text|在不使用外部库的情况下，在每个字段后添加新行：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4603292|log.Println(
++++++++++++strings.Replace(
++++++++++++++++fmt.Sprintf("%25#v",+post),+",+",+"\n",+-1))|code-block|syntax|javascript|4603293|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Without using external libraries and with new line after each field:

<pre><code>log.Println(
 strings.Replace(
 fmt.Sprintf("%#v", post), ", ", "\n", -1))
</code></pre>

blocks|key|4603310|text|我喜欢litter。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|4603311|来自他们的自述文件：|4603312|type+Person+struct+{
++Name+++string
++Age++++int
++Parent+*Person
}

litter.Dump(Person{
++Name:+++"Bob",
++Age:++++20,
++Parent:+&Person{
++++Name:+"Jane",
++++Age:++50,
++},
})|code-block|syntax|javascript|4603313|Sdump在测试中非常方便：|style|CODE|4603314|func+TestSearch(t+*testing.T)+{
++result+:=+DoSearch()

++actual+:=+litterOpts.Sdump(result)
++expected,+err+:=+ioutil.ReadFile("testdata.txt")
++if+err+!=+nil+{
++++//+First+run,+write+test+data+since+it+doesn't+exist
++++++++if+!os.IsNotExist(err)+{
++++++t.Error(err)
++++}
++++ioutil.Write("testdata.txt",+actual,+0644)
++++actual+=+expected
++}
++if+expected+!=+actual+{
++++t.Errorf("Expected+%25s,+got+%25s",+expected,+actual)
++}
}|4603315|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/sanity-io/litter^0|3|6|0|0|0|0|0|5|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@$A|Z|B|10|1|11]]|C|$]]|$1|D|3|E|5|6|7|12|8|@]|9|@]|C|$]]|$1|F|3|G|5|H|7|13|8|@]|9|@]|C|$I|J]]|$1|K|3|L|5|6|7|14|8|@$A|15|B|16|M|N]]|9|@]|C|$]]|$1|O|3|P|5|H|7|17|8|@]|9|@]|C|$I|J]]|$1|Q|3|-4|5|6|7|18|8|@]|9|@]|C|$]]]|R|$S|$5|T|U|V|C|$W|X]]]]

I like <a href="https://github.com/sanity-io/litter" rel="noreferrer">litter</a>.

From their readme:

<pre><code>type Person struct {
 Name string
 Age int
 Parent *Person
}

litter.Dump(Person{
 Name: "Bob",
 Age: 20,
 Parent: &amp;Person{
 Name: "Jane",
 Age: 50,
 },
})
</code></pre>

<code>Sdump</code> is pretty handy in tests: 

<pre><code>func TestSearch(t *testing.T) {
 result := DoSearch()

 actual := litterOpts.Sdump(result)
 expected, err := ioutil.ReadFile("testdata.txt")
 if err != nil {
 // First run, write test data since it doesn't exist
 if !os.IsNotExist(err) {
 t.Error(err)
 }
 ioutil.Write("testdata.txt", actual, 0644)
 actual = expected
 }
 if expected != actual {
 t.Errorf("Expected %s, got %s", expected, actual)
 }
}
</code></pre>

blocks|key|97116|text|我的2cents是使用json.MarshalIndent+--令人惊讶的是没有人建议这样做，因为它是最简单的。例如：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|97117|func+prettyPrint(i+interface{})+string+{
++++s,+_+:=+json.MarshalIndent(i,+"",+"\t")
++++return+string(s)
}|code-block|syntax|javascript|97118|没有外部的dep和结果，输出格式很好。|97119|entityMap^0|B|I|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|S|8|@]|D|@]|E|$]]|$1|M|3|-4|5|6|7|T|8|@]|D|@]|E|$]]]|N|$]]

my 2cents would be to use <code>json.MarshalIndent</code> -- surprised this isn't suggested, as it is the most straightforward. for example:

<pre><code>func prettyPrint(i interface{}) string {
 s, _ := json.MarshalIndent(i, "", "\t")
 return string(s)
}
</code></pre>

no external deps and results in nicely formatted output.

blocks|key|4603401|text|当您有更复杂的结构时，可能需要在打印之前转换为JSON：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4603402|//+Convert+structs+to+JSON.
data,+err+:=+json.Marshal(myComplexStruct)
fmt.Printf("%25s\n",+data)|code-block|syntax|javascript|4603403|来源：https://gist.github.com/tetsuok/4942960|offset|length|4603404|entityMap|0|LINK|mutability|MUTABLE|url|https://gist.github.com/tetsuok/4942960^0|0|0|3|13|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@]|9|@$I|V|J|W|1|X]]|A|$]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|R]]]]

When you have more complex structures, you might need to convert to JSON before printing:

<pre><code>// Convert structs to JSON.
data, err := json.Marshal(myComplexStruct)
fmt.Printf("%s\n", data)
</code></pre>

Source: <a href="https://gist.github.com/tetsuok/4942960" rel="nofollow noreferrer">https://gist.github.com/tetsuok/4942960</a>

blocks|key|4603422|text|fmt.Println("%25%2Bv",+structure+variable)|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|4603423|更好的方法是在名为“commons”(也许)的包中为字符串"%25%2Bv“创建一个全局常量，并在代码中的任何位置使用它|unstyled|4603424|//In+commons+package
const+STRUCTURE_DATA_FMT+=+"%25%2Bv"

//In+your+code+everywhere
fmt.Println(commons.STRUCTURE_DATA_FMT,+structure+variable)|4603425|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|L|8|@]|9|@]|A|$]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$B|C]]|$1|I|3|-4|5|F|7|N|8|@]|9|@]|A|$]]]|J|$]]

<pre><code>fmt.Println("%+v", structure variable)
</code></pre>

A better way to do this would be to create a global constant for the string "%+v" in a package called "commons"(maybe) and use it everywhere in your code

<pre><code>//In commons package
const STRUCTURE_DATA_FMT = "%+v"

//In your code everywhere
fmt.Println(commons.STRUCTURE_DATA_FMT, structure variable)
</code></pre>

blocks|key|4603487|text|或者，尝试使用此函数PrettyPrint()|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|4603488|//+print+the+contents+of+the+obj
func+PrettyPrint(data+interface{})+{
++++var+p+[]byte
++++//++++var+err+:=+error
++++p,+err+:=+json.MarshalIndent(data,+"",+"\t")
++++if+err+!=+nil+{
++++++++fmt.Println(err)
++++++++return
++++}
++++fmt.Printf("%25s+\n",+p)
}|code-block|syntax|javascript|4603489|为了使用它，除了fmt和encoding/json之外，您不需要任何额外的包，只需要一个引用、指向您创建的结构的指针或文本。|4603490|要使用它，只需接受你的结构，在main或任何你所在的包中初始化它，并将它传递给PrettyPrint()。|4603491|type+Prefix+struct+{
++++Network+string
++++Mask++++int
}

func+valueStruct()+{
++++//+struct+as+a+value
++++var+nw+Prefix
++++nw.Network+=+"10.1.1.0"
++++nw.Mask+=+24
++++fmt.Println("###+struct+as+a+pointer+###")
++++PrettyPrint(&nw)
}|4603492|它的输出将是|4603493|###+struct+as+a+pointer+###
{
++++"Network":+"10.1.1.0",
++++"Mask":+24
}+|4603494|使用代码here。|4603495|entityMap|0|LINK|mutability|MUTABLE|url|https://play.golang.org/p/YZn4hHXYdw^0|A|D|0|0|8|3|C|D|0|13|D|0|0|0|0|4|4|0|0^^$0|@$1|2|3|4|5|6|7|14|8|@$9|15|A|16|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|17|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|18|8|@$9|19|A|1A|B|C]|$9|1B|A|1C|B|C]]|D|@]|E|$]]|$1|M|3|N|5|6|7|1D|8|@$9|1E|A|1F|B|C]]|D|@]|E|$]]|$1|O|3|P|5|H|7|1G|8|@]|D|@]|E|$I|J]]|$1|Q|3|R|5|6|7|1H|8|@]|D|@]|E|$]]|$1|S|3|T|5|H|7|1I|8|@]|D|@]|E|$I|J]]|$1|U|3|V|5|6|7|1J|8|@]|D|@$9|1K|A|1L|1|1M]]|E|$]]|$1|W|3|-4|5|6|7|1N|8|@]|D|@]|E|$]]]|X|$Y|$5|Z|10|11|E|$12|13]]]]

Alternatively, try using this function <code>PrettyPrint()</code>

<pre><code>// print the contents of the obj
func PrettyPrint(data interface{}) {
 var p []byte
 // var err := error
 p, err := json.MarshalIndent(data, "", "\t")
 if err != nil {
 fmt.Println(err)
 return
 }
 fmt.Printf("%s \n", p)
}
</code></pre>

In order to use this you do not need any additional packages with the exception of <code>fmt</code> and <code>encoding/json</code>, just a reference, pointer to, or literal of the struct you have created. 

To use just take your struct, initialize it in main or whatever package you are in and pass it into <code>PrettyPrint()</code>. 

<pre><code>type Prefix struct {
 Network string
 Mask int
}

func valueStruct() {
 // struct as a value
 var nw Prefix
 nw.Network = "10.1.1.0"
 nw.Mask = 24
 fmt.Println("### struct as a pointer ###")
 PrettyPrint(&amp;nw)
}
</code></pre>

It's output would be

<pre><code>### struct as a pointer ###
{
 "Network": "10.1.1.0",
 "Mask": 24
} 
</code></pre>

Play around with the code <a href="https://play.golang.org/p/YZn4hHXYdw" rel="noreferrer">here</a>.

blocks|key|97310|text|这些包中的大多数都依赖于反射包来实现这些事情。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|97311|​|97312|📷|atomic|offset|length|97313|fmt.Sprintf()使用标准库的->函数(p+*pp)+printArg(arg+interface{}，verb+rune|97314|转至第638行->+https://golang.org/src/fmt/print.go|97315|反射：|97316|https://golang.org/pkg/reflect/|97317|示例代码：|97318|https://github.com/donutloop/toolkit/blob/master/debugutil/prettysprint.go|97319|entityMap|0|IMAGE|mutability|IMMUTABLE|imageUrl|https://ask.qcloudimg.com/http-save/yehe-900000/96bd87ff658f2429b6075ff2e77bc9ea.png|imageAlt|1|LINK|MUTABLE|url|https://golang.org/src/fmt/print.go|2|3^0|0|0|0|1|0|0|0|A|Z|1|0|0|0|V|2|0|0|0|22|3|0^^$0|@$1|2|3|4|5|6|7|1A|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|1B|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|1C|8|@]|9|@$G|1D|H|1E|1|1F]]|A|$]]|$1|I|3|J|5|6|7|1G|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|1H|8|@]|9|@$G|1I|H|1J|1|1K]]|A|$]]|$1|M|3|N|5|6|7|1L|8|@]|9|@]|A|$]]|$1|O|3|P|5|6|7|1M|8|@]|9|@$G|1N|H|1O|1|1P]]|A|$]]|$1|Q|3|R|5|6|7|1Q|8|@]|9|@]|A|$]]|$1|S|3|T|5|6|7|1R|8|@]|9|@$G|1S|H|1T|1|1U]]|A|$]]|$1|U|3|-4|5|6|7|1V|8|@]|9|@]|A|$]]]|V|$W|$5|X|Y|Z|A|$10|11|12|-4]]|13|$5|14|Y|15|A|$16|17]]|18|$5|14|Y|15|A|$16|P]]|19|$5|14|Y|15|A|$16|T]]]]

Most of these packages are relying on the reflect package to make such things possible.

<a href="https://i.stack.imgur.com/3h9Kr.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/3h9Kr.png" alt="enter image description here"></a> 

fmt.Sprintf() is using -> func (p *pp) printArg(arg interface{}, verb rune) of standard lib

Go to line 638 -> <a href="https://golang.org/src/fmt/print.go" rel="nofollow noreferrer">https://golang.org/src/fmt/print.go</a>

Reflection:

<a href="https://golang.org/pkg/reflect/" rel="nofollow noreferrer">https://golang.org/pkg/reflect/</a>

Example code:

<a href="https://github.com/donutloop/toolkit/blob/master/debugutil/prettysprint.go" rel="nofollow noreferrer">https://github.com/donutloop/toolkit/blob/master/debugutil/prettysprint.go</a>

blocks|key|4603585|text|fmt.Printf("%25%2Bv\n",+project)|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|4603586|这是打印详细信息的基本方法|unstyled|4603587|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|J|8|@]|9|@]|A|$]]|$1|G|3|-4|5|F|7|K|8|@]|9|@]|A|$]]]|H|$]]

<pre><code>fmt.Printf("%+v\n", project)
</code></pre>

This is the basic way of printing the details

blocks|key|97342|text|++++type+Response+struct+{
++++++++UserId+int++++`json:"userId"`
++++++++Id+++++int++++`json:"id"`
++++++++Title++string+`json:"title"`
++++++++Body+++string+`json:"body"`
++++}

++++func+PostsGet()+gin.HandlerFunc+{
++++++++return+func(c+*gin.Context)+{
++++++++++++xs,+err+:=+http.Get("https://jsonplaceholder.typicode.com/posts")
++++++++++++if+err+!=+nil+{
++++++++++++++++log.Println("The+HTTP+request+failed+with+error:+",+err)
++++++++++++}
++++++++++++data,+_+:=+ioutil.ReadAll(xs`enter+code+here`.Body)


++++++++++++//+this+will+print+the+struct+in+console++++++++++++
++++++++++++fmt.Println(string(data))


++++++++++++//+this+is+to+send+as+response+for+the+API
++++++++++++bytes+:=+[]byte(string(data))
++++++++++++var+res+[]Response
++++++++++++json.Unmarshal(bytes,+&res)

++++++++++++c.JSON(http.StatusOK,+res)
++++++++}
++++}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|97343|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> type Response struct {
 UserId int `json:"userId"`
 Id int `json:"id"`
 Title string `json:"title"`
 Body string `json:"body"`
 }

 func PostsGet() gin.HandlerFunc {
 return func(c *gin.Context) {
 xs, err := http.Get("https://jsonplaceholder.typicode.com/posts")
 if err != nil {
 log.Println("The HTTP request failed with error: ", err)
 }
 data, _ := ioutil.ReadAll(xs`enter code here`.Body)


 // this will print the struct in console 
 fmt.Println(string(data))


 // this is to send as response for the API
 bytes := []byte(string(data))
 var res []Response
 json.Unmarshal(bytes, &amp;res)

 c.JSON(http.StatusOK, res)
 }
 }
</code></pre>

blocks|key|97370|text|非常简单，我没有数据和提交的结构，所以我修改了|type|unstyled|depth|inlineStyleRanges|entityRanges|data|97371|package+main

import+(
++++"fmt"
)

type+Project+struct+{
++++Id++++++int64+++`json:"project_id"`
++++Title+++string++`json:"title"`
++++Name++++string++`json:"name"`
++++Data++++string++`json:"data"`
++++Commits+string++`json:"commits"`
}

func+main()+{
++++p+:=+Project{
++++1,
++++"First",
++++"Ankit",
++++"your+data",
++++"Commit+message",
++++}
++++fmt.Println(p)
}|code-block|syntax|javascript|97372|对于学习，您可以从此处获得帮助：https://gobyexample.com/structs|offset|length|97373|entityMap|0|LINK|mutability|MUTABLE|url|https://gobyexample.com/structs^0|0|0|G|V|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@]|9|@$I|V|J|W|1|X]]|A|$]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|R]]]]

very simple 
I don't have the structure of Data and Commits So I changed the

<pre><code>package main

import (
 "fmt"
)

type Project struct {
 Id int64 `json:"project_id"`
 Title string `json:"title"`
 Name string `json:"name"`
 Data string `json:"data"`
 Commits string `json:"commits"`
}

func main() {
 p := Project{
 1,
 "First",
 "Ankit",
 "your data",
 "Commit message",
 }
 fmt.Println(p)
}
</code></pre>

For learning you can take help from here : <a href="https://gobyexample.com/structs" rel="nofollow noreferrer">https://gobyexample.com/structs</a>

blocks|key|4603647|text|也许这不应该应用于生产请求，但如果您处于调试模式，我建议您遵循以下方法。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4603648|marshalledText,+_+:=+json.MarshalIndent(inputStruct,+"",+"+")
fmt.Println(string(marshalledText))|code-block|syntax|javascript|4603649|这导致以json格式格式化数据，提高了可读性。|4603650|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Maybe this shouldn't be applied for production requests but if you are on debugging mode I suggest you follow the below approach. 

<pre><code>marshalledText, _ := json.MarshalIndent(inputStruct, "", " ")
fmt.Println(string(marshalledText))
</code></pre>

This results in formatting the data in json format with increased readability.

blocks|key|4603667|text|要将结构打印为JSON，请执行以下操作：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4603668|fmt.Printf("%25#v\n",+yourProject)|code-block|syntax|javascript|4603669|也可以使用(如上所述)：|4603670|fmt.Printf("%25%2Bv\n",+yourProject)|4603671|但是第二个选项打印不带"“的字符串值，因此更难阅读。|4603672|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

To print the struct as JSON:
<pre><code>fmt.Printf(&quot;%#v\n&quot;, yourProject)
</code></pre>
Also possible with (as it was mentioned above):
<pre><code>fmt.Printf(&quot;%+v\n&quot;, yourProject)
</code></pre>
But the second option prints string values without &quot;&quot; so it is harder to read.

blocks|key|4603699|text|使用fmt包输出非常方便：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4603700|fmt.Printf("%25%2Bv+\n",+yourProject)|code-block|syntax|javascript|4603701|如果想要查看sturct的完整类型，可以使用#+replace+%2B：|4603702|fmt.Printf("%25#v+\n",+yourProject)+|4603703|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

It is very convenient to use package fmt to output:
<pre><code>fmt.Printf(&quot;%+v \n&quot;, yourProject)
</code></pre>
if you want to see the full type of the sturct, you can use # replace + :
<pre><code>fmt.Printf(&quot;%#v \n&quot;, yourProject) 
</code></pre>

blocks|key|4603727|text|有时，将结构打印为有效的Go代码(等同于go/ast+)可能很方便。为此，https://github.com/hexops/valast做了很好的工作：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|4603728|package+main

import+(
++++"fmt"

++++"github.com/hexops/valast"
)

type+ProjectData+struct+{
++++Title+++string+`json:"title"`
++++Name++++string+`json:"name"`
++++Data++++string+`json:"data"`
++++Commits+string+`json:"commits"`
}

type+Project+struct+{
++++Id+++int64++++++++`json:"project_id"`
++++Data+*ProjectData+`json:"data"`
}

func+main()+{
++++p+:=+Project{
++++++++Id:+1,
++++++++Data:+&ProjectData{
++++++++++++Title:+++"Test",
++++++++++++Name:++++"Mihai",
++++++++++++Data:++++"Some+data",
++++++++++++Commits:+"Test+Message",
++++++++},
++++}
++++fmt.Println(valast.String(p))
}|code-block|syntax|javascript|4603729|输出：|4603730|go+run+main.go+
Project{Id:+1,+Data:+&ProjectData{
++++++++Title:+++"Test",
++++++++Name:++++"Mihai",
++++++++Data:++++"Some+data",
++++++++Commits:+"Test+Message",
}}|4603731|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/hexops/valast^0|K|6|11|W|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@$9|X|A|Y|B|C]]|D|@$9|Z|A|10|1|11]]|E|$]]|$1|F|3|G|5|H|7|12|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|13|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|14|8|@]|D|@]|E|$I|J]]|$1|O|3|-4|5|6|7|15|8|@]|D|@]|E|$]]]|P|$Q|$5|R|S|T|E|$U|V]]]]

Sometimes, it might be handy to print the struct as valid Go code (the <code>go/ast</code> equivalent). For this purpose, <a href="https://github.com/hexops/valast" rel="nofollow noreferrer">https://github.com/hexops/valast</a> does a great job:
<pre><code>package main

import (
 &quot;fmt&quot;

 &quot;github.com/hexops/valast&quot;
)

type ProjectData struct {
 Title string `json:&quot;title&quot;`
 Name string `json:&quot;name&quot;`
 Data string `json:&quot;data&quot;`
 Commits string `json:&quot;commits&quot;`
}

type Project struct {
 Id int64 `json:&quot;project_id&quot;`
 Data *ProjectData `json:&quot;data&quot;`
}

func main() {
 p := Project{
 Id: 1,
 Data: &amp;ProjectData{
 Title: &quot;Test&quot;,
 Name: &quot;Mihai&quot;,
 Data: &quot;Some data&quot;,
 Commits: &quot;Test Message&quot;,
 },
 }
 fmt.Println(valast.String(p))
}
</code></pre>
Output:
<pre><code>go run main.go 
Project{Id: 1, Data: &amp;ProjectData{
 Title: &quot;Test&quot;,
 Name: &quot;Mihai&quot;,
 Data: &quot;Some data&quot;,
 Commits: &quot;Test Message&quot;,
}}
</code></pre>

blocks|key|97517|text|您可以先执行json+mashal，然后将其打印为字符串。在那里你可以看到完整的结构值。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|97518|package+main

import+"fmt"
import+"json"

type+Project+struct+{
++++Id+int64+`json:"project_id"`
++++Title+string+`json:"title"`
++++Name+string+`json:"name"`
}

func+main()+{
++++o+:=+Project{Id:+4,+Name:+"hello",+Title:+"world"}
++++om,+_+:=+json.marshal(o)
++++log.Printf("%25s\n",+string(om))
}|code-block|syntax|javascript|97519|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

You can do the json mashal first and print it as a string. There you can see it the whole struct value completely.
<pre><code>package main

import &quot;fmt&quot;
import &quot;json&quot;

type Project struct {
 Id int64 `json:&quot;project_id&quot;`
 Title string `json:&quot;title&quot;`
 Name string `json:&quot;name&quot;`
}

func main() {
 o := Project{Id: 4, Name: &quot;hello&quot;, Title: &quot;world&quot;}
 om, _ := json.marshal(o)
 log.Printf(&quot;%s\n&quot;, string(om))
}
</code></pre>

blocks|key|4603810|text|一个简单的问题有很多答案。我不妨把我的帽子扔到拳台上去。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4603811|package+main

import+"fmt"

type+Project+struct+{
++++Id++++int64++`json:"project_id"`
++++Title+string+`json:"title"`
++++Name++string+`json:"name"`
++++//Data++++Data++++`json:"data"`
++++//Commits+Commits+`json:"commits"`
}

var+(
++++Testy+Project
)

func+dump_project(foo+Project)+{
++++fmt.Println("==+Dump+Project+Struct+====")
++++fmt.Printf("Id:+%25d\n",+foo.Id)
++++fmt.Println("Title:+",+foo.Title)
++++fmt.Printf("Name:+%25v\n",+foo.Name)
}

func+main()+{
++++fmt.Println("hello+from+go")
++++Testy.Id+=+3
++++Testy.Title+=+"yo"
++++Testy.Name+=+"my+name"
++++fmt.Println(Testy)
++++dump_project(Testy)
}|code-block|syntax|javascript|4603812|各种打印方法的输出|4603813|hello+from+go
{3+yo+my+name}
==+Dump+Project+Struct+====
Id:+3
Title:++yo
Name:+my+name|4603814|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

A lot of answers for a simple question. I might as well throw my hat in the ring.
<pre><code>package main

import &quot;fmt&quot;

type Project struct {
 Id int64 `json:&quot;project_id&quot;`
 Title string `json:&quot;title&quot;`
 Name string `json:&quot;name&quot;`
 //Data Data `json:&quot;data&quot;`
 //Commits Commits `json:&quot;commits&quot;`
}

var (
 Testy Project
)

func dump_project(foo Project) {
 fmt.Println(&quot;== Dump Project Struct ====&quot;)
 fmt.Printf(&quot;Id: %d\n&quot;, foo.Id)
 fmt.Println(&quot;Title: &quot;, foo.Title)
 fmt.Printf(&quot;Name: %v\n&quot;, foo.Name)
}

func main() {
 fmt.Println(&quot;hello from go&quot;)
 Testy.Id = 3
 Testy.Title = &quot;yo&quot;
 Testy.Name = &quot;my name&quot;
 fmt.Println(Testy)
 dump_project(Testy)
}
</code></pre>
The output of the various print methods
<pre><code>hello from go
{3 yo my name}
== Dump Project Struct ====
Id: 3
Title: yo
Name: my name
</code></pre>

How can I print (in the console) the <code>Id</code>, <code>Title</code>, <code>Name</code>, etc. of this struct in Golang?

<pre><code>type Project struct {
 Id int64 `json:"project_id"`
 Title string `json:"title"`
 Name string `json:"name"`
 Data Data `json:"data"`
 Commits Commits `json:"commits"`
}
</code></pre>

How to print struct variables in console?

数据结构

JSON

如何(在控制台中)在Golang中打印此结构的Id、Title、Name等？type Project struct {    Id      int64   `json:"project_id"`    Title   string  `json:"title"`    Name    string  `json:"n...

问如何在控制台中打印结构变量？
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