Go結合Gin匯出Mysql資料到Excel表格

2022-08-04 22:04:55

1、實現目標

Golang 使用excelize 匯出表格到瀏覽器下載或者儲存到本地。
後續匯入的話也會寫到這裡

2、使用的庫

go get github.com/xuri/excelize/v2

Git地址：
https://github.com/qax-os/excelize
檔案地址：
https://xuri.me/excelize/zh-hans/base/installation.html

3、專案目錄

go-excel
├─ app
│  ├─ excelize
│  │  └─ excelize.go
│  ├─ model
│  │  └─ sysUser.go
│  └─ service
│     └─ userService.go
├─ common
│  └─ mysql.go
├─ go.mod
├─ go.sum
├─ main.go
└─ setting.json

4、主要程式碼編寫

gin還不會老師們可以看：https://blog.csdn.net/bei_FengBoby/article/details/124847078
讀取組態檔是用的viper

4.1、excelize.go(主要工具類)

ExportExcelByStruct 函數是從網路上直接copy的，研究他這個寫法花了好一會兒，所以也寫上去了，提供大家學習

import (
	"fmt"
	"math/rand"
	"net/url"
	"reflect"
	"strconv"
	"time"

	"github.com/gin-gonic/gin"
	"github.com/xuri/excelize/v2"
)

var (
	defaultSheetName = "Sheet1" //預設Sheet名稱
	defaultHeight    = 25.0     //預設行高度
)

type lzExcelExport struct {
	file      *excelize.File
	sheetName string //可定義預設sheet名稱
}

func NewMyExcel() *lzExcelExport {
	return &lzExcelExport{file: createFile(), sheetName: defaultSheetName}
}

//匯出基本的表格
func (l *lzExcelExport) ExportToPath(params []map[string]string, data []map[string]interface{}, path string) (string, error) {
	l.export(params, data)
	name := createFileName()
	filePath := path + "/" + name
	err := l.file.SaveAs(filePath)
	return filePath, err
}

//匯出到瀏覽器。此處使用的gin框架 其他框架可自行修改ctx
func (l *lzExcelExport) ExportToWeb(params []map[string]string, data []map[string]interface{}, c *gin.Context) {
	l.export(params, data)
	buffer, _ := l.file.WriteToBuffer()
	//設定檔案型別
	c.Header("Content-Type", "application/vnd.ms-excel;charset=utf8")
	//設定檔名稱
	c.Header("Content-Disposition", "attachment; filename="+url.QueryEscape(createFileName()))
	_, _ = c.Writer.Write(buffer.Bytes())
}

//設定首行
func (l *lzExcelExport) writeTop(params []map[string]string) {
	topStyle, _ := l.file.NewStyle(`{"font":{"bold":true},"alignment":{"horizontal":"center","vertical":"center"}}`)
	var word = 'A'
	//首行寫入
	for _, conf := range params {
		title := conf["title"]
		width, _ := strconv.ParseFloat(conf["width"], 64)
		line := fmt.Sprintf("%c1", word)
		//設定標題
		_ = l.file.SetCellValue(l.sheetName, line, title)
		//列寬
		_ = l.file.SetColWidth(l.sheetName, fmt.Sprintf("%c", word), fmt.Sprintf("%c", word), width)
		//設定樣式
		_ = l.file.SetCellStyle(l.sheetName, line, line, topStyle)
		word++
	}
}

//寫入資料
func (l *lzExcelExport) writeData(params []map[string]string, data []map[string]interface{}) {
	lineStyle, _ := l.file.NewStyle(`{"alignment":{"horizontal":"center","vertical":"center"}}`)
	//資料寫入
	var j = 2 //資料開始行數
	for i, val := range data {
		//設定行高
		_ = l.file.SetRowHeight(l.sheetName, i+1, defaultHeight)
		//逐列寫入
		var word = 'A'
		for _, conf := range params {
			valKey := conf["key"]
			line := fmt.Sprintf("%c%v", word, j)
			isNum := conf["is_num"]

			//設定值
			if isNum != "0" {
				valNum := fmt.Sprintf("'%v", val[valKey])
				_ = l.file.SetCellValue(l.sheetName, line, valNum)
			} else {
				_ = l.file.SetCellValue(l.sheetName, line, val[valKey])
			}

			//設定樣式
			_ = l.file.SetCellStyle(l.sheetName, line, line, lineStyle)
			word++
		}
		j++
	}
	//設定行高 尾行
	_ = l.file.SetRowHeight(l.sheetName, len(data)+1, defaultHeight)
}

func (l *lzExcelExport) export(params []map[string]string, data []map[string]interface{}) {
	l.writeTop(params)
	l.writeData(params, data)
}

func createFile() *excelize.File {
	f := excelize.NewFile()
	// 建立一個預設工作表
	sheetName := defaultSheetName
	index := f.NewSheet(sheetName)
	// 設定工作簿的預設工作表
	f.SetActiveSheet(index)
	return f
}

func createFileName() string {
	name := time.Now().Format("2006-01-02-15-04-05")
	rand.Seed(time.Now().UnixNano())
	return fmt.Sprintf("excle-%v-%v.xlsx", name, rand.Int63n(time.Now().Unix()))
}

//excel匯出(資料來源為Struct) []interface{}
func (l *lzExcelExport) ExportExcelByStruct(titleList []string, data []interface{}, fileName string, sheetName string, c *gin.Context) error {
	l.file.SetSheetName("Sheet1", sheetName)
	header := make([]string, 0)
	for _, v := range titleList {
		header = append(header, v)
	}
	rowStyleID, _ := l.file.NewStyle(`{"font":{"color":"#666666","size":13,"family":"arial"},"alignment":{"vertical":"center","horizontal":"center"}}`)
	_ = l.file.SetSheetRow(sheetName, "A1", &header)
	_ = l.file.SetRowHeight("Sheet1", 1, 30)
	length := len(titleList)
	headStyle := Letter(length)
	var lastRow string
	var widthRow string
	for k, v := range headStyle {

		if k == length-1 {

			lastRow = fmt.Sprintf("%s1", v)
			widthRow = v
		}
	}
	if err := l.file.SetColWidth(sheetName, "A", widthRow, 30); err != nil {
		fmt.Print("錯誤--", err.Error())
	}
	rowNum := 1
	for _, v := range data {

		t := reflect.TypeOf(v)
		fmt.Print("--ttt--", t.NumField())
		value := reflect.ValueOf(v)
		row := make([]interface {
		}, 0)
		for l := 0; l < t.NumField(); l++ {

			val := value.Field(l).Interface()
			row = append(row, val)
		}
		rowNum++
		err := l.file.SetSheetRow(sheetName, "A"+strconv.Itoa(rowNum), &row)
		_ = l.file.SetCellStyle(sheetName, fmt.Sprintf("A%d", rowNum), fmt.Sprintf("%s", lastRow), rowStyleID)
		if err != nil {
			return err
		}
	}
	disposition := fmt.Sprintf("attachment; filename=%s.xlsx", url.QueryEscape(fileName))
	c.Writer.Header().Set("Content-Type", "application/octet-stream")
	c.Writer.Header().Set("Content-Disposition", disposition)
	c.Writer.Header().Set("Content-Transfer-Encoding", "binary")
	c.Writer.Header().Set("Access-Control-Expose-Headers", "Content-Disposition")
	return l.file.Write(c.Writer)
}

// Letter 遍歷a-z
func Letter(length int) []string {
	var str []string
	for i := 0; i < length; i++ {
		str = append(str, string(rune('A'+i)))
	}
	return str
}

4.2、userService.go（接受請求）

其中匯出的函數都已經測試是ok的，可以直接用，資料改成自己的就好，
注意的事項裡面我也寫了，避雷！！

import (
	"go-excel/app/excelize"
	"go-excel/app/model"
	config "go-excel/common"
	"github.com/gin-gonic/gin"
)



//獲取所有使用者資料-excel
func GetAllUserExportToWeb(ctx *gin.Context) {
	var users []model.TUser
	db := config.GetDB()
	db.Find(&users)

	//定義首行標題
	dataKey := make([]map[string]string, 0)
	dataKey = append(dataKey, map[string]string{
		"key":    "id",
		"title":  "索引",
		"width":  "20",
		"is_num": "0",
	})
	dataKey = append(dataKey, map[string]string{
		"key":    "username",
		"title":  "使用者名稱",
		"width":  "20",
		"is_num": "0",
	})
	dataKey = append(dataKey, map[string]string{
		"key":    "remark",
		"title":  "備註",
		"width":  "20",
		"is_num": "0",
	})

	//填充資料
	data := make([]map[string]interface{}, 0)
	if len(users) > 0 {
		for _, v := range users {
			data = append(data, map[string]interface{}{
				"id":       v.ID,
				"username": v.Username,
				"remark":   v.Remark,
			})
		}
	}
	ex := excelize.NewMyExcel()
  
	// ex.ExportToWeb(dataKey, data, ctx)

	//儲存到D槽
	ex.ExportToPath(dataKey, data, "D:/")
}

//excel 匯出
func GetUserExcelByMap(ctx *gin.Context) {
	var users []model.TUser
	db := config.GetDB()
	db.Find(&users)

	titles := []string{"ID", "使用者名稱", "備註"}

	ex := excelize.NewMyExcel()

	var datas []interface{}
	for _, v := range users {
		//這裡最好新建一個struct 和titles一致，不然users裡面的多餘的欄位也會寫進去
		datas = append(datas, model.TUser{
			ID:       v.ID,
			Username: v.Username,
			Remark:   v.Remark,
		})
	}
	ex.ExportExcelByStruct(titles, datas, "使用者資料", "使用者", ctx)
}