Go-Excelize API 源码阅读（二十三）——SetDocProps、GetDocProps

func (f *File) SetDocProps(docProperties *DocProperties) error

err := f.SetDocProps(&excelize.DocProperties{    Category:       "category",    ContentStatus:  "Draft",    Created:        "2019-06-04T22:00:10Z",    Creator:        "Go Excelize",    Description:    "This file created by Go Excelize",    Identifier:     "xlsx",    Keywords:       "Spreadsheet",    LastModifiedBy: "Go Author",    Modified:       "2019-06-04T22:00:10Z",    Revision:       "0",    Subject:        "Test Subject",    Title:          "Test Title",    Language:       "en-US",    Version:        "1.0.0",})

func (f *File) SetDocProps(docProperties *DocProperties) (err error) {  var (    core               *decodeCoreProperties    newProps           *xlsxCoreProperties    fields             []string    output             []byte    immutable, mutable reflect.Value    field, val         string  )
  core = new(decodeCoreProperties)  if err = f.xmlNewDecoder(bytes.NewReader(namespaceStrictToTransitional(f.readXML(defaultXMLPathDocPropsCore)))).    Decode(core); err != nil && err != io.EOF {    err = fmt.Errorf("xml decode error: %s", err)    return  }  newProps, err = &xlsxCoreProperties{    Dc:             NameSpaceDublinCore,    Dcterms:        NameSpaceDublinCoreTerms,    Dcmitype:       NameSpaceDublinCoreMetadataInitiative,    XSI:            NameSpaceXMLSchemaInstance,    Title:          core.Title,    Subject:        core.Subject,    Creator:        core.Creator,    Keywords:       core.Keywords,    Description:    core.Description,    LastModifiedBy: core.LastModifiedBy,    Language:       core.Language,    Identifier:     core.Identifier,    Revision:       core.Revision,    ContentStatus:  core.ContentStatus,    Category:       core.Category,    Version:        core.Version,  }, nil  if core.Created != nil {    newProps.Created = &xlsxDcTerms{Type: core.Created.Type, Text: core.Created.Text}  }  if core.Modified != nil {    newProps.Modified = &xlsxDcTerms{Type: core.Modified.Type, Text: core.Modified.Text}  }  fields = []string{    "Category", "ContentStatus", "Creator", "Description", "Identifier", "Keywords",    "LastModifiedBy", "Revision", "Subject", "Title", "Language", "Version",  }  immutable, mutable = reflect.ValueOf(*docProperties), reflect.ValueOf(newProps).Elem()  for _, field = range fields {    if val = immutable.FieldByName(field).String(); val != "" {      mutable.FieldByName(field).SetString(val)    }  }  if docProperties.Created != "" {    newProps.Created = &xlsxDcTerms{Type: "dcterms:W3CDTF", Text: docProperties.Created}  }  if docProperties.Modified != "" {    newProps.Modified = &xlsxDcTerms{Type: "dcterms:W3CDTF", Text: docProperties.Modified}  }  output, err = xml.Marshal(newProps)  f.saveFileList(defaultXMLPathDocPropsCore, output)
  return}

  core = new(decodeCoreProperties)  if err = f.xmlNewDecoder(bytes.NewReader(namespaceStrictToTransitional(f.readXML(defaultXMLPathDocPropsCore)))).    Decode(core); err != nil && err != io.EOF {    err = fmt.Errorf("xml decode error: %s", err)    return  }

  defaultXMLPathDocPropsCore  = "docProps/core.xml"

  newProps, err = &xlsxCoreProperties{    Dc:             NameSpaceDublinCore,    Dcterms:        NameSpaceDublinCoreTerms,    Dcmitype:       NameSpaceDublinCoreMetadataInitiative,    XSI:            NameSpaceXMLSchemaInstance,    Title:          core.Title,    Subject:        core.Subject,    Creator:        core.Creator,    Keywords:       core.Keywords,    Description:    core.Description,    LastModifiedBy: core.LastModifiedBy,    Language:       core.Language,    Identifier:     core.Identifier,    Revision:       core.Revision,    ContentStatus:  core.ContentStatus,    Category:       core.Category,    Version:        core.Version,  }, nil    if core.Created != nil {    newProps.Created = &xlsxDcTerms{Type: core.Created.Type, Text: core.Created.Text}  }  if core.Modified != nil {    newProps.Modified = &xlsxDcTerms{Type: core.Modified.Type, Text: core.Modified.Text}  }    fields = []string{    "Category", "ContentStatus", "Creator", "Description", "Identifier", "Keywords",    "LastModifiedBy", "Revision", "Subject", "Title", "Language", "Version",  }  immutable, mutable = reflect.ValueOf(*docProperties), reflect.ValueOf(newProps).Elem()  for _, field = range fields {    if val = immutable.FieldByName(field).String(); val != "" {      mutable.FieldByName(field).SetString(val)    }  }  if docProperties.Created != "" {    newProps.Created = &xlsxDcTerms{Type: "dcterms:W3CDTF", Text: docProperties.Created}  }  if docProperties.Modified != "" {    newProps.Modified = &xlsxDcTerms{Type: "dcterms:W3CDTF", Text: docProperties.Modified}  }  output, err = xml.Marshal(newProps)  f.saveFileList(defaultXMLPathDocPropsCore, output)

// GetDocProps provides a function to get document core properties.func (f *File) GetDocProps() (ret *DocProperties, err error) {  core := new(decodeCoreProperties)
  if err = f.xmlNewDecoder(bytes.NewReader(namespaceStrictToTransitional(f.readXML(defaultXMLPathDocPropsCore)))).    Decode(core); err != nil && err != io.EOF {    err = fmt.Errorf("xml decode error: %s", err)    return  }  ret, err = &DocProperties{    Category:       core.Category,    ContentStatus:  core.ContentStatus,    Creator:        core.Creator,    Description:    core.Description,    Identifier:     core.Identifier,    Keywords:       core.Keywords,    LastModifiedBy: core.LastModifiedBy,    Revision:       core.Revision,    Subject:        core.Subject,    Title:          core.Title,    Language:       core.Language,    Version:        core.Version,  }, nil  if core.Created != nil {    ret.Created = core.Created.Text  }  if core.Modified != nil {    ret.Modified = core.Modified.Text  }  return}