实现打印级别且带图片的Excel 方案

导出二维数据excel，其实很简单，使用cvs就可以了。但是如果导出格式复杂带样式还带图片的怎么办？客户的要求有时就是这么变态。呵呵。如果使用.net，微软提供的有库，使用php好像也有现成的有库。我大致对这些库进行了解，都可以实现我们的需求。可惜我现在使用的golang没有那么库支持，所以只好裸搞了。

Excel格式分为两种，第一种是封闭式，不知道使用啥格式，比如office 2003使用的格式，扩展名为*.xsl。另一种是开放式的，使用的是Open XML技术，比如office 2007 以后的版本，好在现在已经2014了，7年过去，大部分人都已经用到office 2012，即使国产的wps也早已经完美支持Open XML 了。 所以不用考虑兼容问题了。

这次我的解决方案就是从Open XML 入手。通过对Open XML学习，解决思路大致可分为3步骤：

第一步：使用支持Open XML 的软件，比如 office 2010制作一个我们想要的Excel，保存扩展名名为xlsx。

第二步：把xlsx修改扩展名为 zip,解压后使用占位符，修改里面相应的XML文件，然后压缩，再把扩展名修改为xlsx。这个压缩文件我们可称为导出模板。

第三步：使用程序动态解压，替换占位符，再压缩。其中对图片的处理，是把图片保存到相应文件夹以及相应XML，千言万语，不如代码更加直接，实现代码如下：

func (c Order) Excel(pageIndex int, pageSize int, sortField string, sortOrder string, customId int64, state string, orderTime string) revel.Result {
    sql := "select a.name A,b.name B,e.name C,d.name D,c.name E,a.order_time F,a.money G,a.state H,a.image I,a.width J,a.height K,a.area L,a.unit M,a.amount N,a.price O,f.alias P,a.remarks Q from ad_order a,ad_custom b,ad_product c,ad_stuff d,ad_stuff_cat e,ad_user f where a.product_id=c.id and c.stuff_id=d.id and d.cat_id=e.id and a.custom_id=b.id and a.user_id=f.id and a.del_state='未删' %s %s %s order by a.id desc"
    sql = fmt.Sprintf(sql, fmt.Sprintf("and a.custom_id=%d", customId), "%s", "%s")
    if state != "" {
        sql = fmt.Sprintf(sql, fmt.Sprintf("and a.state='%s'", state), "%s")
    } else {
        sql = fmt.Sprintf(sql, "", "%s")
    }
    if orderTime != "" {
        sql = fmt.Sprintf(sql, fmt.Sprintf("and a.order_time='%s'", orderTime))
    } else {
        sql = fmt.Sprintf(sql, "")
    }
    orders, err := Orm.Query(sql)
    if err != nil {
        return c.RenderJson(models.Message{State: "failure", Msg: err.Error()})
    }
    rows := make([]Rows, 0)
    col := 17
    for i := 1; i <= len(orders); i++ {
        row := Rows{}
        row.RowId = i + 1
        for k := 0; k < col; k++ {
            row.Columns = append(row.Columns, Columns{R: fmt.Sprintf("%s%d", string(ABC[k]), i+1), V: i*col + k})
        }
        rows = append(rows, row)
    }
    vmlDrawings := make([]VmlDrawing, 0)
    sharedStrings := make([]string, 0)
    sharedStrings = append(sharedStrings, "订单名称")
    sharedStrings = append(sharedStrings, "客户名称")
    sharedStrings = append(sharedStrings, "产品目录")
    sharedStrings = append(sharedStrings, "产品材料")
    sharedStrings = append(sharedStrings, "产品名称")
    sharedStrings = append(sharedStrings, "订单日期")
    sharedStrings = append(sharedStrings, "金额")
    sharedStrings = append(sharedStrings, "收费状态")
    sharedStrings = append(sharedStrings, "产品图片")
    sharedStrings = append(sharedStrings, "宽度(米)")
    sharedStrings = append(sharedStrings, "高度(米)")
    sharedStrings = append(sharedStrings, "面积")
    sharedStrings = append(sharedStrings, "单位")
    sharedStrings = append(sharedStrings, "数量")
    sharedStrings = append(sharedStrings, "单价")
    sharedStrings = append(sharedStrings, "经手人")
    sharedStrings = append(sharedStrings, "备注")
    for i, row := range orders {
        if string(row["I"]) != "" {
            img := string(row["I"])
            vmlDrawing := VmlDrawing{}
            vmlDrawing.Index = i
            vmlDrawing.Id = img[:strings.Index(img, ".")]
            vmlDrawing.Name = fmt.Sprintf("S%s", img)
            vmlDrawing.RowBegin = i + 1
            vmlDrawing.RowEnd = i + 2
            vmlDrawings = append(vmlDrawings, vmlDrawing)
        }
        sharedStrings = append(sharedStrings, string(row["A"])) //订单名称
        sharedStrings = append(sharedStrings, string(row["B"])) //客户名称
        sharedStrings = append(sharedStrings, string(row["C"])) //产品目录
        sharedStrings = append(sharedStrings, string(row["D"])) //产品材料
        sharedStrings = append(sharedStrings, string(row["E"])) //产品名称
        sharedStrings = append(sharedStrings, string(row["F"])) //订单日期

        f1, _ := strconv.ParseFloat(string(row["G"]), 32)
        sharedStrings = append(sharedStrings, fmt.Sprintf("%.2f", f1)) //金额
        sharedStrings = append(sharedStrings, string(row["H"]))        //收费状态
        sharedStrings = append(sharedStrings, "")                      //产品图片

        f2, _ := strconv.ParseFloat(string(row["J"]), 32)
        sharedStrings = append(sharedStrings, fmt.Sprintf("%.2f", f2)) //宽度(米)

        f3, _ := strconv.ParseFloat(string(row["K"]), 32)
        sharedStrings = append(sharedStrings, fmt.Sprintf("%.2f", f3)) //高度(米)

        f4, _ := strconv.ParseFloat(string(row["L"]), 32)
        sharedStrings = append(sharedStrings, fmt.Sprintf("%.4f", f4)) //面积
        sharedStrings = append(sharedStrings, string(row["M"]))        //单位
        sharedStrings = append(sharedStrings, string(row["N"]))        //数量

        f5, _ := strconv.ParseFloat(string(row["O"]), 32)
        sharedStrings = append(sharedStrings, fmt.Sprintf("%.2f", f5)) //单价
        sharedStrings = append(sharedStrings, string(row["P"]))        //经手人
        sharedStrings = append(sharedStrings, string(row["Q"]))        //备注
    }
    basePath := revel.BasePath
    basePathPrefix := fpath.Join(basePath, fpath.FromSlash("app/templates"))

    file, _ := os.Create(fpath.Join(basePathPrefix, fpath.FromSlash(fmt.Sprintf("%s.xlsx", "orders"))))
    w := zip.NewWriter(file)
    defer w.Close()
    r, _ := zip.OpenReader(fpath.Join(basePathPrefix, fpath.FromSlash(fmt.Sprintf("%s.xlsx", "order"))))
    defer r.Close()
    for _, f := range r.File {
        switch f.Name {
        case "xl/worksheets/sheet1.xml":
            buf := new(bytes.Buffer)
            rc, _ := f.Open()
            data, _ := ioutil.ReadAll(rc)
            rc.Close()
            tmpl, _ := template.New("sheet").Parse(string(data))
            tmpl.Execute(buf, rows)
            ff, _ := w.Create(f.Name)
            ff.Write(buf.Bytes())
            break
        case "xl/sharedStrings.xml":
            buf := new(bytes.Buffer)
            rc, _ := f.Open()
            data, _ := ioutil.ReadAll(rc)
            rc.Close()
            tmpl, _ := template.New("sharedStrings").Parse(string(data))
            tmpl.Execute(buf, sharedStrings)
            ff, _ := w.Create(f.Name)
            ff.Write(buf.Bytes())
            break
        case "xl/drawings/_rels/vmlDrawing1.vml.rels":
            buf := new(bytes.Buffer)
            rc, _ := f.Open()
            data, _ := ioutil.ReadAll(rc)
            rc.Close()
            tmpl, _ := template.New("vmlDrawing1.vml").Parse(string(data))
            tmpl.Execute(buf, vmlDrawings)
            ff, _ := w.Create(f.Name)
            ff.Write(buf.Bytes())
            break
        case "xl/drawings/vmlDrawing1.vml":
            buf := new(bytes.Buffer)
            rc, _ := f.Open()
            data, _ := ioutil.ReadAll(rc)
            rc.Close()
            tmpl, _ := template.New("vmlDrawing1").Parse(string(data))
            tmpl.Execute(buf, vmlDrawings)
            ff, _ := w.Create(f.Name)
            ff.Write(buf.Bytes())
            basePath := revel.BasePath
            basePathPrefix := fpath.Join(basePath, fpath.FromSlash("public/upload"))
            for _, v := range vmlDrawings {
                fsmall := fpath.Join(basePathPrefix, fpath.FromSlash(v.Name))
                file, _ := os.Open(fsmall)
                data, _ := ioutil.ReadAll(file)
                ff, _ := w.Create(fmt.Sprintf("xl/media/%s", v.Name))
                ff.Write(data)
            }
            break
        default:
            ff, _ := w.Create(f.Name)
            rc, _ := f.Open()
            data, _ := ioutil.ReadAll(rc)
            ff.Write(data)
            rc.Close()
        }
    }
    return c.RenderFile(file, revel.Attachment)
}

最后吐槽一下，博客园插入code，既然没有golang。