c# - 在列上添加特定的自动过滤器

Question

我正在尝试对列设置过滤器。这是我在 Interop 中的做法:

private void CheckMasterFile(string path) {
    var xlApp = new Excel.Application();
    var xlWorkbook = xlApp.Workbooks.Open(path);
    Excel._Worksheet xlWorksheet = xlWorkbook.Sheets[1];

    foreach (var project in projects) {
        if (string.IsNullOrEmpty(project.ProjectID.Value)) {
            continue;
        }

        var xlRange = xlWorksheet.UsedRange;
        if (xlWorksheet.AutoFilter != null) {
            xlWorksheet.AutoFilterMode = false;
        }
        xlRange.AutoFilter(Field: 2, Criteria1: project.ProjectID.Value);
        var result = xlRange.SpecialCells(Excel.XlCellType.xlCellTypeVisible, Type.Missing);//only shows filtered values
        double sum = 0;

        foreach (Excel.Range row in result.Rows) {
            if (row.Cells[2, 2].Value2() != null) {
                if (!NOT_ALLOWED_RUBRIQUES.Contains((string)row.Cells[2, 8].Value2())) {//check if rubrique is allowed or not
                    //finish method
                }
            }
        }
    }
    xlWorkbook.Close(SaveChanges: false);
    xlApp.Quit();
}

但是我可以在 EPPlus 中使用自动过滤器做一些事情的唯一方法是启用或禁用它，而不是根据特定值过滤列。像这样:

sheet.Cells["A RANGE HERE"].AutoFilter = true;

所以我在这里想要实现的是根据特定值过滤一个巨大的 Excel 文件，然后只显示具有这些值的行。

Answer 1

如果我明白你在问什么，那不是 EPPlus 的意图。它旨在生成 excel 文件作为端点。您正在尝试做的事情似乎实际上是在使用 Excel 作为您的分析工具。

如果您真的想对输出列应用过滤器，那么您不必手动进行，因为 EPPlus 本身并不应用过滤器。所以像这样的事情(必须自己处理)。但是您(生成器)仍有责任实际执行分析 - 在这种情况下最后一个 linq 查询:

[TestMethod]
public void AutoFilter_Test()
{
    //http://stackoverflow.com/questions/32723483/adding-a-specific-autofilter-on-a-column

    //Throw in some data
    var datatable = new DataTable("tblData");
    datatable.Columns.AddRange(new[] { new DataColumn("Col1", typeof(int)), new DataColumn("Col2", typeof(int)), new DataColumn("Col3", typeof(object)) });

    for (var i = 0; i < 10; i++)
    {
        var row = datatable.NewRow(); row[0] = i; row[1] = i * 10;row[2] = Path.GetRandomFileName();
        datatable.Rows.Add(row);
    }

    //Create a test file
    var fi = new FileInfo(@"c:\temp\autofilter.xlsx");
    if (fi.Exists)
        fi.Delete();

    using (var pck = new ExcelPackage(fi))
    {
        var worksheet = pck.Workbook.Worksheets.Add("Sheet1");
        worksheet.Cells.LoadFromDataTable(datatable, true);

        var range = worksheet.Cells["A1:C10"];
        range.AutoFilter = true;

        pck.Save();
    }

    //Needed prior save in order for the XML to be generated
    using (var pck = new ExcelPackage(fi))
    {
        var worksheet = pck.Workbook.Worksheets.First();

        //Get reference to the worksheet xml for proper namespace
        var xdoc = worksheet.WorksheetXml;
        var nsm = new XmlNamespaceManager(xdoc.NameTable);
        nsm.AddNamespace("default", xdoc.DocumentElement.NamespaceURI);

        //Create the filters themselves
        var filter1 = xdoc.CreateNode(XmlNodeType.Element, "filter", xdoc.DocumentElement.NamespaceURI);
        var att = xdoc.CreateAttribute("val");
        att.Value = "40";
        filter1.Attributes.Append(att);

        var filter2 = xdoc.CreateNode(XmlNodeType.Element, "filter", xdoc.DocumentElement.NamespaceURI);
        att = xdoc.CreateAttribute("val");
        att.Value = "50";
        filter2.Attributes.Append(att);

        //Add filters to the collection
        var filters = xdoc.CreateNode(XmlNodeType.Element, "filters", xdoc.DocumentElement.NamespaceURI);
        filters.AppendChild(filter1);
        filters.AppendChild(filter2);

        //Create the parent filter container
        var filterColumn = xdoc.CreateNode(XmlNodeType.Element, "filterColumn", xdoc.DocumentElement.NamespaceURI);
        att = xdoc.CreateAttribute("colId");
        att.Value = "1";
        filterColumn.Attributes.Append(att);
        filterColumn.AppendChild(filters);

        //Now add it to the autoFilters node
        var autoFilter = xdoc.SelectSingleNode("/default:worksheet/default:autoFilter", nsm);
        autoFilter.AppendChild(filterColumn);

        //Have to manually hide rows based on criteria
        worksheet.Cells
            .Where(cell =>
                cell.Address.StartsWith("B") 
                && cell.Value is double 
                && (double) cell.Value != 40d 
                && (double) cell.Value != 50d)
            .Select(cell => cell.Start.Row)
            .ToList()
            .ForEach(r => worksheet.Row(r).Hidden = true);

        pck.Save();
    }
}

输出