Go Excelize API原始碼解讀GetSheetViewOptions與SetPageLayout

2022-08-18 18:02:53

一、Go-Excelize簡介

Excelize 是 Go 語言編寫的用於操作 Office Excel 檔案基礎庫，基於 ECMA-376，ISO/IEC 29500 國際標準。
可以使用它來讀取、寫入由 Microsoft Excel™ 2007 及以上版本建立的電子試算表檔案。
支援 XLAM / XLSM / XLSX / XLTM / XLTX 等多種檔案格式，高度相容帶有樣式、圖片(表)、透視表、切片器等複雜元件的檔案，並提供流式讀寫 API，用於處理包含大規模資料的工作簿。
可應用於各類報表平臺、雲端計算、邊緣計算等系統。使用本類庫要求使用的 Go 語言為 1.15 或更高版本。

二、 GetSheetViewOptions

func (f *File) GetSheetViewOptions(sheet string, viewIndex int, opts ...SheetViewOptionPtr) error

根據給定的工作表名稱、檢視索引和檢視引數獲取工作表檢視屬性，viewIndex 可以是負數，如果是這樣，則向後計數（-1 代表最後一個檢視）。

例子：獲取名為 Sheet1 的工作表上最後一個檢視的格線屬性設定。

var showGridLines excelize.ShowGridLines
err = f.GetSheetViewOptions("Sheet1", -1, &amp;showGridLines)

廢話少說，直接上程式碼：

func (f *File) GetSheetViewOptions(name string, viewIndex int, opts ...SheetViewOptionPtr) error {
	view, err := f.getSheetView(name, viewIndex)
	if err != nil {
		return err
	}
	for _, opt := range opts {
		opt.getSheetViewOption(view)
	}
	return nil
}

這段程式碼邏輯是否簡單，簡單說一下：先根據工作表檢視索引獲取工作表檢視，然後遍歷不定長引數opts。

然後引數opt做主語，工作表檢視做引數，然後獲取檢視的各引數內容。具體實現方法如下：

三、 SetPageLayout

func (f *File) SetPageLayout(sheet string, opts ...PageLayoutOption) error

根據給定的工作表名稱和頁面佈局引數設定工作表的頁面佈局屬性。目前支援設定的頁面佈局屬性：

通過 BlackAndWhite 方法設定單色列印 true 或 false，預設值為 false 關閉。
通過 FirstPageNumber 方法設定頁面起始頁碼，預設為自動。
通過 PageLayoutOrientation 方法設定頁面佈局方向，預設頁面佈局方向為“縱向”。下面的表格是 Excelize 中頁面佈局方向 PageLayoutOrientation 引數的列表：

引數	方向
OrientationPortrait	縱向
OrientationLandscape	橫向

通過 PageLayoutPaperSize 方法設定頁面紙張大小，預設頁面佈局大小為“信紙 8½ × 11 英寸”。下面的表格是 Excelize 中頁面佈局大小和索引 PageLayoutPaperSize 引數的關係對照：

//     Index | Paper Size
//    -------+-----------------------------------------------
//       1   | Letter paper (8.5 in. by 11 in.)
//       2   | Letter small paper (8.5 in. by 11 in.)
//       3   | Tabloid paper (11 in. by 17 in.)
//       4   | Ledger paper (17 in. by 11 in.)
//       5   | Legal paper (8.5 in. by 14 in.)
//       6   | Statement paper (5.5 in. by 8.5 in.)
//       7   | Executive paper (7.25 in. by 10.5 in.)
//       8   | A3 paper (297 mm by 420 mm)
//       9   | A4 paper (210 mm by 297 mm)
//       10  | A4 small paper (210 mm by 297 mm)
//       11  | A5 paper (148 mm by 210 mm)
//       12  | B4 paper (250 mm by 353 mm)
//       13  | B5 paper (176 mm by 250 mm)
//       14  | Folio paper (8.5 in. by 13 in.)
//       15  | Quarto paper (215 mm by 275 mm)
//       16  | Standard paper (10 in. by 14 in.)
//       17  | Standard paper (11 in. by 17 in.)
//       18  | Note paper (8.5 in. by 11 in.)
//       19  | #9 envelope (3.875 in. by 8.875 in.)
//       20  | #10 envelope (4.125 in. by 9.5 in.)
//       21  | #11 envelope (4.5 in. by 10.375 in.)
//       22  | #12 envelope (4.75 in. by 11 in.)
//       23  | #14 envelope (5 in. by 11.5 in.)
//       24  | C paper (17 in. by 22 in.)
//       25  | D paper (22 in. by 34 in.)
//       26  | E paper (34 in. by 44 in.)
//       27  | DL envelope (110 mm by 220 mm)
//       28  | C5 envelope (162 mm by 229 mm)
//       29  | C3 envelope (324 mm by 458 mm)
//       30  | C4 envelope (229 mm by 324 mm)
//       31  | C6 envelope (114 mm by 162 mm)
//       32  | C65 envelope (114 mm by 229 mm)
//       33  | B4 envelope (250 mm by 353 mm)
//       34  | B5 envelope (176 mm by 250 mm)
//       35  | B6 envelope (176 mm by 125 mm)
//       36  | Italy envelope (110 mm by 230 mm)
//       37  | Monarch envelope (3.875 in. by 7.5 in.).
//       38  | 6 3/4 envelope (3.625 in. by 6.5 in.)
//       39  | US standard fanfold (14.875 in. by 11 in.)
//       40  | German standard fanfold (8.5 in. by 12 in.)
//       41  | German legal fanfold (8.5 in. by 13 in.)
//       42  | ISO B4 (250 mm by 353 mm)
//       43  | Japanese postcard (100 mm by 148 mm)
//       44  | Standard paper (9 in. by 11 in.)
//       45  | Standard paper (10 in. by 11 in.)
//       46  | Standard paper (15 in. by 11 in.)
//       47  | Invite envelope (220 mm by 220 mm)
//       50  | Letter extra paper (9.275 in. by 12 in.)
//       51  | Legal extra paper (9.275 in. by 15 in.)
//       52  | Tabloid extra paper (11.69 in. by 18 in.)
//       53  | A4 extra paper (236 mm by 322 mm)
//       54  | Letter transverse paper (8.275 in. by 11 in.)
//       55  | A4 transverse paper (210 mm by 297 mm)
//       56  | Letter extra transverse paper (9.275 in. by 12 in.)
//       57  | SuperA/SuperA/A4 paper (227 mm by 356 mm)
//       58  | SuperB/SuperB/A3 paper (305 mm by 487 mm)
//       59  | Letter plus paper (8.5 in. by 12.69 in.)
//       60  | A4 plus paper (210 mm by 330 mm)
//       61  | A5 transverse paper (148 mm by 210 mm)
//       62  | JIS B5 transverse paper (182 mm by 257 mm)
//       63  | A3 extra paper (322 mm by 445 mm)
//       64  | A5 extra paper (174 mm by 235 mm)
//       65  | ISO B5 extra paper (201 mm by 276 mm)
//       66  | A2 paper (420 mm by 594 mm)
//       67  | A3 transverse paper (297 mm by 420 mm)
//       68  | A3 extra transverse paper (322 mm by 445 mm)
//       69  | Japanese Double Postcard (200 mm x 148 mm)
//       70  | A6 (105 mm x 148 mm)
//       71  | Japanese Envelope Kaku #2
//       72  | Japanese Envelope Kaku #3
//       73  | Japanese Envelope Chou #3
//       74  | Japanese Envelope Chou #4
//       75  | Letter Rotated (11in x 8 1/2 11 in)
//       76  | A3 Rotated (420 mm x 297 mm)
//       77  | A4 Rotated (297 mm x 210 mm)
//       78  | A5 Rotated (210 mm x 148 mm)
//       79  | B4 (JIS) Rotated (364 mm x 257 mm)
//       80  | B5 (JIS) Rotated (257 mm x 182 mm)
//       81  | Japanese Postcard Rotated (148 mm x 100 mm)
//       82  | Double Japanese Postcard Rotated (148 mm x 200 mm)
//       83  | A6 Rotated (148 mm x 105 mm)
//       84  | Japanese Envelope Kaku #2 Rotated
//       85  | Japanese Envelope Kaku #3 Rotated
//       86  | Japanese Envelope Chou #3 Rotated
//       87  | Japanese Envelope Chou #4 Rotated
//       88  | B6 (JIS) (128 mm x 182 mm)
//       89  | B6 (JIS) Rotated (182 mm x 128 mm)
//       90  | (12 in x 11 in)
//       91  | Japanese Envelope You #4
//       92  | Japanese Envelope You #4 Rotated
//       93  | PRC 16K (146 mm x 215 mm)
//       94  | PRC 32K (97 mm x 151 mm)
//       95  | PRC 32K(Big) (97 mm x 151 mm)
//       96  | PRC Envelope #1 (102 mm x 165 mm)
//       97  | PRC Envelope #2 (102 mm x 176 mm)
//       98  | PRC Envelope #3 (125 mm x 176 mm)
//       99  | PRC Envelope #4 (110 mm x 208 mm)
//       100 | PRC Envelope #5 (110 mm x 220 mm)
//       101 | PRC Envelope #6 (120 mm x 230 mm)
//       102 | PRC Envelope #7 (160 mm x 230 mm)
//       103 | PRC Envelope #8 (120 mm x 309 mm)
//       104 | PRC Envelope #9 (229 mm x 324 mm)
//       105 | PRC Envelope #10 (324 mm x 458 mm)
//       106 | PRC 16K Rotated
//       107 | PRC 32K Rotated
//       108 | PRC 32K(Big) Rotated
//       109 | PRC Envelope #1 Rotated (165 mm x 102 mm)
//       110 | PRC Envelope #2 Rotated (176 mm x 102 mm)
//       111 | PRC Envelope #3 Rotated (176 mm x 125 mm)
//       112 | PRC Envelope #4 Rotated (208 mm x 110 mm)
//       113 | PRC Envelope #5 Rotated (220 mm x 110 mm)
//       114 | PRC Envelope #6 Rotated (230 mm x 120 mm)
//       115 | PRC Envelope #7 Rotated (230 mm x 160 mm)
//       116 | PRC Envelope #8 Rotated (309 mm x 120 mm)
//       117 | PRC Envelope #9 Rotated (324 mm x 229 mm)
//       118 | PRC Envelope #10 Rotated (458 mm x 324 mm)

通過 FitToHeight 方法設定頁面縮放調整頁寬，預設值為 1。
通過 FitToWidth 方法設定頁面縮放調整頁高，預設值為 1。
通過 PageLayoutScale 方法設定頁面縮放比例，取值範圍 10 至 400，即縮放 10% 至 400%，預設值為 100 正常尺寸。
例如，將名為 Sheet1 的工作表頁面佈局設定為單色列印、起始頁碼為 2、橫向、使用 A4(小) 210 × 297 毫米紙張、調整為 2 頁寬、2 頁高並縮放 50%：

f := excelize.NewFile()
if err := f.SetPageLayout(
    "Sheet1",
    excelize.BlackAndWhite(true),
    excelize.FirstPageNumber(2),
    excelize.PageLayoutOrientation(excelize.OrientationLandscape),
    excelize.PageLayoutPaperSize(10),
    excelize.FitToHeight(2),
    excelize.FitToWidth(2),
    excelize.PageLayoutScale(50),
); err != nil {
    fmt.Println(err)
}

廢話少說，直接上原始碼：

func (f *File) SetPageLayout(sheet string, opts ...PageLayoutOption) error {
	s, err := f.workSheetReader(sheet)
	if err != nil {
		return err
	}
	ps := s.PageSetUp
	if ps == nil {
		ps = new(xlsxPageSetUp)
		s.PageSetUp = ps
	}
	for _, opt := range opts {
		opt.setPageLayout(ps)
	}
	return err
}

先讀取工作表，然後獲取工作表的PageSetUp。

根據微軟檔案PageSetup 物件包含作為特性的所有頁面設定屬性（左邊距、下邊距、紙張大小等）。

如果這個物件為空，就新建一個xlsxPageSetUp型別的物件：