过滤数据透视表

GcExcel 能够让你在数据透视表中过滤出特定的值。你可以通过 IPivotItem 接口的 setVisible 方法来隐藏行字段或是页面，也可以利用 IPivotField 接口的 getPivotFilters 方法，这可以让你向数据透视表的字段中增加标签、数值以及日期类型的过滤器，具体是通过向 IPivotFilters 接口的 add 方法传递一个 PivotFilterType 枚举参数实现的。

更进一步地，GcExcel 还提供了 IPivotTable 接口下的 setAllowMultipleFilters 方法，使得在同一 PivotField 上同时应用标签和数值过滤成为可能。该方法的默认设定值为 true，意味着允许多重过滤。但若你将该方法的值设为 false，则意味着后设置的过滤器会覆盖先前的设置。

type=warning
注意: 当 setAllowMultipleFilters 的值由 true 更改为 false 时，这一操作将会影响所有的 IPivotField。在这种情况下，如果某个 IPivotField 同时设置了标签过滤器和数值过滤器，GcExcel 会将这两种过滤器都清除掉。

GcExcel 还提供了几种清除过滤器的方法：ClearLabelFilter 专门用来移除标签过滤器；clearValueFilter 则负责清除数值过滤器；而 clearAllFilters 如其名所示，能够一次性清除字段上设置的所有过滤器。

type=warning
注意: 如果你尝试通过 add 方法同时添加两个同类型的标签过滤器或数值过滤器，后添加的那个过滤器将会自动替换掉先添加的那个，不会存在两个相同类型的过滤器共存的情况。

type=warning
注意: IPivotFilter 接口里的多数方法都是仅供读取的，唯有 WholeDayFilter 方法例外，它允许读写操作。然而，直接修改 WholeDayFilter 值并不会自动促使当前的数据透视表进行刷新。所以，为了确保过滤结果的更新或刷新，你应当手动调用 IPivotTable 接口所提供的 update 或者 refresh 方法。

应用过滤器

请参考以下示例代码来使用 Visible 属性隐藏行字段或页面：

// Create a new workbook.
Workbook workbook = new Workbook();

// Add data for the pivot table.
Object sourceData = new Object[][]{
        {"Order ID", "Product", "Category", "Amount", "Date", "Country"},
        {1, "Bose 785593-0050", "Consumer Electronics", 4270, new GregorianCalendar(2018, 0, 6), "United States"},
        {2, "Canon EOS 1500D", "Consumer Electronics", 8239, new GregorianCalendar(2018, 0, 7), "United Kingdom"},
        {3, "Haier 394L 4Star", "Consumer Electronics", 617, new GregorianCalendar(2018, 0, 8), "United States"},
        {4, "IFB 6.5 Kg FullyAuto", "Consumer Electronics", 8384, new GregorianCalendar(2018, 0, 10), "Canada"},
        {5, "Mi LED 40inch", "Consumer Electronics", 2626, new GregorianCalendar(2018, 0, 10), "Germany"},
        {6, "Sennheiser HD 4.40-BT", "Consumer Electronics", 3610, new GregorianCalendar(2018, 0, 11), "United States"},
        {7, "Iphone XR", "Mobile", 9062, new GregorianCalendar(2018, 0, 11), "Australia"},
        {8, "OnePlus 7Pro", "Mobile", 6906, new GregorianCalendar(2018, 0, 16), "New Zealand"},
        {9, "Redmi 7", "Mobile", 2417, new GregorianCalendar(2018, 0, 16), "France"},
        {10, "Samsung S9", "Mobile", 7431, new GregorianCalendar(2018, 0, 16), "Canada"},
        {11, "OnePlus 7Pro", "Mobile", 8250, new GregorianCalendar(2018, 0, 16), "Germany"},
        {12, "Redmi 7", "Mobile", 7012, new GregorianCalendar(2018, 0, 18), "United States"},
        {13, "Bose 785593-0050", "Consumer Electronics", 1903, new GregorianCalendar(2018, 0, 20), "Germany"},
        {14, "Canon EOS 1500D", "Consumer Electronics", 2824, new GregorianCalendar(2018, 0, 22), "Canada"},
        {15, "Haier 394L 4Star", "Consumer Electronics", 6946, new GregorianCalendar(2018, 0, 24), "France"},
};

// Access first worksheet.
IWorksheet worksheet = workbook.getWorksheets().get(0);
        
// Add values to the range.
worksheet.getRange("G1:L16").setValue(sourceData);
        
// Set column width.
worksheet.getRange("G:L").setColumnWidth(15);
        
// Create pivot cache.
IPivotCache pivotcache = workbook.getPivotCaches().create(worksheet.getRange("G1:L16"));
        
// Add data to the pivot table.
IPivotTable pivottable = worksheet.getPivotTables().add(pivotcache, worksheet.getRange("A1"), "pivottable1");
        
// Set number format.
worksheet.getRange("J1:J16").setNumberFormat("$#,##0.00");

// Configure pivot table's fields.
IPivotField field_Product = pivottable.getPivotFields().get(1);
field_Product.setOrientation(PivotFieldOrientation.RowField);

IPivotField field_Amount = pivottable.getPivotFields().get(3);
field_Amount.setOrientation(PivotFieldOrientation.DataField);
field_Amount.setNumberFormat("$#,##0.00");

IPivotField field_Country = pivottable.getPivotFields().get(5);
field_Country.setOrientation(PivotFieldOrientation.PageField);

// Add row field filter.
field_Product.getPivotItems().get("Bose 785593-0050").setVisible(false);
field_Product.getPivotItems().get("Haier 394L 4Star").setVisible(false);
field_Product.getPivotItems().get("Iphone XR").setVisible(false);

// Add page filter.
field_Country.getPivotItems().get("United States").setVisible(false);
field_Country.getPivotItems().get("Canada").setVisible(false);

worksheet.getRange("A:B").getEntireColumn().autoFit();
    
// Save WorkBook.
workbook.save("FilterPivotTable.xlsx");

应用标签过滤器

请参考以下示例代码，根据项目名称中包含 "mi" 的产品来进行过滤：

// Configure pivot table's fields.
var field_Category = pivottable.getPivotFields().get("Category");
field_Category.setOrientation(PivotFieldOrientation.ColumnField);

var field_Product = pivottable.getPivotFields().get("Product");
field_Product.setOrientation(PivotFieldOrientation.RowField);

var field_Amount = pivottable.getPivotFields().get("Amount");
field_Amount.setOrientation(PivotFieldOrientation.DataField);
field_Amount.setNumberFormat("$#,##0.00");

// Filter for products where the product name contains 'mi'.
field_Product.getPivotFilters().add(PivotFilterType.CaptionContains, "mi");

worksheet.getRange("A:D").getEntireColumn().autoFit();

// Save the workbook.
workbook.save("PivotLabelFilter.xlsx");

应用数值过滤器

请参考示例代码，根据数值来过滤产品：

// Configure pivot table's fields.
var field_Category = pivottable.getPivotFields().get("Category");
field_Category.setOrientation(PivotFieldOrientation.ColumnField);

var field_Product = pivottable.getPivotFields().get("Product");
field_Product.setOrientation(PivotFieldOrientation.RowField);

var field_Amount = pivottable.getPivotFields().get("Amount");
field_Amount.setOrientation(PivotFieldOrientation.DataField);
field_Amount.setNumberFormat("$#,##0.00");

PivotFilterOptions options = new PivotFilterOptions();
options.setAppliedDataField(0);
        
// Filter for products with sales volume greater than 7000.
field_Product.getPivotFilters().add(PivotFilterType.ValueGreaterThan, 7000, null, options);

worksheet.getRange("A:D").getEntireColumn().autoFit();

// Save the workbook.
workbook.save("PivotValueFilter.xlsx");

type=warning
注意：你必须使用 PivotFilterOptions 类的 setAppliedDataField 方法，并结合数值过滤器，来指定依据哪个数据字段进行过滤。

应用日期过滤器

请参考以下示例代码，用于过滤在两个指定日期之间的产品：

// Configure pivot table's fields.
var field_Category = pivottable.getPivotFields().get("Category");
field_Category.setOrientation(PivotFieldOrientation.ColumnField);

var field_Product = pivottable.getPivotFields().get("Product");
field_Product.setOrientation(PivotFieldOrientation.RowField);

var field_Date = pivottable.getPivotFields().get("Date");
field_Date.setOrientation(PivotFieldOrientation.RowField);

var field_Amount = pivottable.getPivotFields().get("Amount");
field_Amount.setOrientation(PivotFieldOrientation.DataField);
field_Amount.setNumberFormat("$#,##0.00");

// Filter for products between two dates.
field_Date.getPivotFilters().add(PivotFilterType.DateBetween, LocalDate.of(2018, 1, 1), LocalDate.of(2018, 1, 15));

worksheet.getRange("A:D").getEntireColumn().autoFit();

// Save the workbook.
workbook.save("PivotDateFilter.xlsx");

应用前10过滤器

请参考示例代码，根据数值来过滤排名前十二的产品：

// Configure pivot table's fields.
var field_Category = pivottable.getPivotFields().get("Category");
field_Category.setOrientation(PivotFieldOrientation.ColumnField);

var field_Product = pivottable.getPivotFields().get("Product");
field_Product.setOrientation(PivotFieldOrientation.RowField);

var field_Amount = pivottable.getPivotFields().get("Amount");
field_Amount.setOrientation(PivotFieldOrientation.DataField);
field_Amount.setNumberFormat("$#,##0.00");

// Filter for top 12 products.
PivotFilterOptions options = new PivotFilterOptions();
options.setIsTop10Type(true);
field_Product.getPivotFilters().add(PivotFilterType.Count, 12, null, options);

worksheet.getRange("A:D").getEntireColumn().autoFit();

// Save the workbook.
workbook.save("PivotTopTenFilter.xlsx");

应用多重过滤器

请参考以下示例代码，使用标签和数值过滤器来共同筛选产品：

// Configure pivot table's fields.
var field_Category = pivottable.getPivotFields().get("Category");
field_Category.setOrientation(PivotFieldOrientation.ColumnField);

var field_Product = pivottable.getPivotFields().get("Product");
field_Product.setOrientation(PivotFieldOrientation.RowField);

var field_Amount = pivottable.getPivotFields().get("Amount");
field_Amount.setOrientation(PivotFieldOrientation.DataField);
field_Amount.setNumberFormat("$#,##0.00");

// Allow adding label filter and value filter to a field at the same time.
pivottable.setAllowMultipleFilters(true);

// Filter for products with sales volume greater than 7000.
PivotFilterOptions options = new PivotFilterOptions();
options.setAppliedDataField(0);
field_Product.getPivotFilters().add(PivotFilterType.ValueGreaterThan, 7000, null, options);

// Filter for products where the product name contains 'mi'.
field_Product.getPivotFilters().add(PivotFilterType.CaptionContains, "mi");

worksheet.getRange("A:D").getEntireColumn().autoFit();

// Save the workbook.
workbook.save("MultipleFilter.xlsx");