在OpenXML(excel)中创建自定义列宽

我是OpenXML（v.2.5）的新手，我可以创建行和单元格，但我需要能够设置列宽，但由于某些原因，我无法正确设置。

没有此代码：

        Columns cols = new Columns();
        Column c1 = new Column()
        {
            CustomWidth = true,
            Width = 20
        };
        cols.Append(c1);
        wspart.Worksheet.Append(cols);

该程序运行并生成一个excel文件罚款。

下面的代码符合并运行，但给我留下了一个损坏的excel文档。当我尝试添加列时，我做错了什么？

    public static void createExcel() //TODO change to private
    {
        //create the spreadsheet document with openxml See https://msdn.microsoft.com/en-us/library/office/ff478153.aspx
        SpreadsheetDocument spreadsheetDoc = SpreadsheetDocument.Create(@"C:'Users'Reid'Documents'BLA'test.xlsx", SpreadsheetDocumentType.Workbook); //TODO change path
        //add a workbook part
        WorkbookPart wbpart = spreadsheetDoc.AddWorkbookPart();
        wbpart.Workbook = new Workbook();
        //add a worksheet part
        WorksheetPart wspart = wbpart.AddNewPart<WorksheetPart>();
        Worksheet ws = new Worksheet(new SheetData());
        wspart.Worksheet = ws;
        //create a new sheets array
        Sheets sheets = spreadsheetDoc.WorkbookPart.Workbook.AppendChild<Sheets>(new Sheets());
        //create a new sheet
        Sheet sheet = new Sheet()
        {
            Id = spreadsheetDoc.WorkbookPart.GetIdOfPart(wspart),
            SheetId = 1,
            Name = "mySheet" //TODO change name
        };
        //add the sheet to the workbook sheet aray
        sheets.Append(sheet);
        SheetData shData = wspart.Worksheet.GetFirstChild<SheetData>();
        //////////////////////////////////row and col widths//////////////////////
        Columns cols = new Columns();
        Column c1 = new Column()
        {
            CustomWidth = true,
            Width = 20
        };
        cols.Append(c1);
        wspart.Worksheet.Append(cols);
        //create the first row
        Row r1 = new Row
        {
            RowIndex = 1,
            CustomHeight = true,
            Height = 71.25 //change height based on info
        };
        shData.Append(r1);
  ////////////////////////cell data/////////////////////////////////
        // In the new row, find the column location to insert a cell in A1.
        Cell refCell = null;
        foreach (Cell cell in r1.Elements<Cell>())
        {
            if (string.Compare(cell.CellReference.Value, "A1", true) > 0)
            {
                refCell = cell;
                break;
            }
        }
        // Add the cell to the cell table at A1.
        Cell newCell = new Cell() {
            CellReference = "A1",
        };
        r1.InsertBefore(newCell, refCell);
        // Set the cell value to be a numeric value of 100.
        newCell.CellValue = new CellValue("100");

        //TODO add in standard things (text that is always the same, headers, logos, etc.)
        //TODO add in dynamic text
        //TODO create and add in barcodes
        //Save and close the document
        wbpart.Workbook.Save();
        spreadsheetDoc.Close();
        //TODO send document to database
    }