- Fix SheetCount count error;

- Optimize deserialization operations;
- README updated, add go version required notice

Author: xuri

README.md

@@ -11,7 +11,7 @@
 
 ## Introduction
 
-Excelize is a library written in pure Golang and providing a set of functions that allow you to write to and read from XLSX files. Support reads and writes XLSX file generated by Office Excel 2007 and later. Support save file without losing original charts of XLSX. The full API docs can be seen using go's built-in documentation tool, or online at [godoc.org](https://godoc.org/github.com/Luxurioust/excelize).
+Excelize is a library written in pure Golang and providing a set of functions that allow you to write to and read from XLSX files. Support reads and writes XLSX file generated by Office Excel 2007 and later. Support save file without losing original charts of XLSX. This library needs Go version 1.8 or later. The full API docs can be seen using go's built-in documentation tool, or online at [godoc.org](https://godoc.org/github.com/Luxurioust/excelize).
 
 ## Basic Usage
 

excelize.go

@@ -13,11 +13,14 @@ import (
 
 // File define a populated XLSX file struct.
 type File struct {
-	checked    map[string]bool
-	XLSX       map[string]string
-	Path       string
-	Sheet      map[string]*xlsxWorksheet
-	SheetCount int
+	checked      map[string]bool
+	ContentTypes *xlsxTypes
+	Path         string
+	Sheet        map[string]*xlsxWorksheet
+	SheetCount   int
+	WorkBook     *xlsxWorkbook
+	WorkBookRels *xlsxWorkbookRels
+	XLSX         map[string]string
 }
 
 // OpenFile take the name of an XLSX file and returns a populated XLSX file
@@ -53,11 +56,10 @@ func OpenReader(r io.Reader) (*File, error) {
 		return nil, err
 	}
 	return &File{
-		Sheet:      make(map[string]*xlsxWorksheet),
 		checked:    make(map[string]bool),
-		XLSX:       file,
-		Path:       "",
+		Sheet:      make(map[string]*xlsxWorksheet),
 		SheetCount: sheetCount,
+		XLSX:       file,
 	}, nil
 }
 

file.go

@@ -3,7 +3,6 @@ package excelize
 import (
 	"archive/zip"
 	"bytes"
-	"encoding/xml"
 	"fmt"
 	"io"
 	"os"
@@ -26,8 +25,8 @@ func CreateFile() *File {
 	file["xl/workbook.xml"] = templateWorkbook
 	file["[Content_Types].xml"] = templateContentTypes
 	return &File{
-		XLSX:  file,
 		Sheet: make(map[string]*xlsxWorksheet),
+		XLSX:  file,
 	}
 }
 
@@ -54,16 +53,10 @@ func (f *File) WriteTo(name string) error {
 func (f *File) Write(w io.Writer) error {
 	buf := new(bytes.Buffer)
 	zw := zip.NewWriter(buf)
-	for path, sheet := range f.Sheet {
-		if sheet == nil {
-			continue
-		}
-		output, err := xml.Marshal(sheet)
-		if err != nil {
-			return err
-		}
-		f.saveFileList(path, replaceWorkSheetsRelationshipsNameSpace(string(output)))
-	}
+	f.contentTypesWriter()
+	f.workbookWriter()
+	f.workbookRelsWriter()
+	f.worksheetWriter()
 	for path, content := range f.XLSX {
 		fi, err := zw.Create(path)
 		if err != nil {

picture.go

@@ -303,8 +303,7 @@ func (f *File) addMedia(file string, ext string) {
 // for relationship parts and the Main Document part.
 func (f *File) setContentTypePartImageExtensions() {
 	var imageTypes = map[string]bool{"jpeg": false, "png": false, "gif": false}
-	var content xlsxTypes
-	xml.Unmarshal([]byte(f.readXML("[Content_Types].xml")), &content)
+	content := f.contentTypesReader()
 	for _, v := range content.Defaults {
 		_, ok := imageTypes[v.Extension]
 		if ok {
@@ -319,30 +318,23 @@ func (f *File) setContentTypePartImageExtensions() {
 			})
 		}
 	}
-	output, _ := xml.Marshal(content)
-	f.saveFileList("[Content_Types].xml", string(output))
 }
 
 // addDrawingContentTypePart provides function to add image part relationships
 // in http://purl.oclc.org/ooxml/officeDocument/relationships/image and
 // appropriate content type.
 func (f *File) addDrawingContentTypePart(index int) {
 	f.setContentTypePartImageExtensions()
-	var content xlsxTypes
-	xml.Unmarshal([]byte(f.readXML("[Content_Types].xml")), &content)
+	content := f.contentTypesReader()
 	for _, v := range content.Overrides {
 		if v.PartName == "/xl/drawings/drawing"+strconv.Itoa(index)+".xml" {
-			output, _ := xml.Marshal(content)
-			f.saveFileList(`[Content_Types].xml`, string(output))
 			return
 		}
 	}
 	content.Overrides = append(content.Overrides, xlsxOverride{
 		PartName:    "/xl/drawings/drawing" + strconv.Itoa(index) + ".xml",
 		ContentType: "application/vnd.openxmlformats-officedocument.drawing+xml",
 	})
-	output, _ := xml.Marshal(content)
-	f.saveFileList("[Content_Types].xml", string(output))
 }
 
 // getSheetRelationshipsTargetByID provides function to get Target attribute