Golang encoding/xml.Encoder.EncodeToken() function example

package encoding/xml

EncodeToken writes the given XML token to the stream. It returns an error if StartElement and EndElement tokens are not properly matched.

EncodeToken does not call Flush, because usually it is part of a larger operation such as Encode or EncodeElement (or a custom Marshaler's MarshalXML invoked during those), and those will call Flush when finished. Callers that create an Encoder and then invoke EncodeToken directly, without using Encode or EncodeElement, need to call Flush when finished to ensure that the XML is written to the underlying writer.

EncodeToken allows writing a ProcInst with Target set to "xml" only as the first token in the stream.

Golang encoding/xml.Encoder.EncodeToken() function usage example

 package main

 import (
 "encoding/xml"
 "fmt"
 "os"
 "reflect"
 )

 type Address struct {
 City, State string
 }
 type Person struct {
 XMLName xml.Name `xml:"person"`
 Id int `xml:"id,attr"`
 FirstName string `xml:"name>first"`
 LastName  string `xml:"name>last"`
 Age int `xml:"age"`
 Height float32  `xml:"height,omitempty"`
 Married bool
 Address
 Comment string `xml:",comment"`
 }

 func main() {
 v := &Person{Id: 13, FirstName: "John", LastName: "Doe", Age: 42}
 v.Comment = " Need more details. "
 v.Address = Address{"Hanga Roa", "Easter Island"}

 encoder := xml.NewEncoder(os.Stdout)

 newtoken := xml.StartElement{
 Name : xml.Name{
 Space: "",
 Local: "location",
 },
 }

 if err := encoder.EncodeToken(newtoken); err != nil {
 fmt.Println(err)
 }


 start := xml.StartElement{
 Name: xml.Name{
 Space: "",
 Local: reflect.Indirect(reflect.ValueOf(v)).Type().Name(),
 },
 Attr: []xml.Attr{{xml.Name{"", "xmlns"}, "http://localhost/xmldoc/2014-09-01/"}},
 }
 if err := encoder.EncodeElement(v, start); err != nil {
 fmt.Println(err)
 }

 }

Output :

<location> <---- newtoken

<Person xmlns="https://socketloop.com/xmldoc/2014-09-01/" id="13"><name><first>John</first><last>Doe</last></name>

<age>42</age><Married>false</Married><City>Hanga Roa</City><State>Easter Island</State>

<!-- Need more details. --></Person>

Reference :

http://golang.org/pkg/encoding/xml/#Encoder.EncodeToken

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