Data Filtering with Golang via C++
AutoFilter Data
AutoFiltering is the quickest way to select only those items from the worksheet that you want to display in a list. The AutoFilter feature allows users to filter items in a list according to a set of criteria. Filters can be based on text, numbers, or dates.
AutoFilter in Microsoft Excel
To activate the AutoFilter feature in Microsoft Excel:
- Click a heading row in a worksheet.
- From the Data menu, select Filter and then AutoFilter.
When you apply an AutoFilter to a worksheet, filter switches (black arrows) appear to the right of the column headings.
- Click a filter arrow to see a list of filter options.
Some of the AutoFilter options are:
| Options | Description |
|---|---|
| All | Show all items in the list once. |
| Custom | Customize filter criteria like contains/not contains |
| Filter by Color | Filters based on filled color |
| Date Filters | Filters rows based on different date criteria |
| Number Filters | Different types of filters on numbers, such as comparisons, averages, and Top 10, etc. |
| Text Filters | Different filters like begins with, ends with, contains, etc. |
| Blanks/Non Blanks | These filters can be implemented through the Text Filter Blank option |
Users manually filter their worksheet data in Microsoft Excel using these options.
AutoFilter with Aspose.Cells
Aspose.Cells provides a class Workbook that represents an Excel file. The Workbook class contains a Worksheets collection that allows access to each worksheet in the Excel file.
A worksheet is represented by the Worksheet class. The Worksheet class provides a wide range of properties and methods to manage worksheets. To create an AutoFilter, use the AutoFilter property of the Worksheet class. The AutoFilter property is an object of the AutoFilter class, which provides the Range property for specifying the range of cells that make up a heading row. An AutoFilter is applied to the range of cells that is the heading row.
In each worksheet, you can specify only one filter range. This limitation is imposed by Microsoft Excel. For custom data filtering, use the AutoFilter.Custom method.
In the example given below, we have created the same AutoFilter using Aspose.Cells as we created using Microsoft Excel in the above section.
Different Types of Filters
Aspose.Cells provides multiple options to apply different types of filters, such as Color Filter, Date Filter, Number Filter, Text Filter, Blank Filters, and Non‑Blank Filters.
Fill Color
Aspose.Cells provides a function AddFillColorFilter to filter data based upon the fill‑color property of the cells. In the example given below, a template file having different fill colors in the first column of the sheet is used to test the color‑filtering function. Sample files can be downloaded from the following links.
Date
Different types of date filters can be implemented, such as filtering all rows that have dates in January 2018. The following sample code demonstrates this filter using the AddDateFilter function. Sample files are given below.
Dynamic Date
Sometimes dynamic filters are required based on date, such as all cells having dates in January irrespective of the year. In this case the DynamicFilter function is used, as shown in the following sample code. Sample files are given below.
Number
Custom filters can be applied using Aspose.Cells, such as selecting cells that have numbers between a given range. The following example demonstrates the usage of the Custom() function to filter numbers. Sample files are given below.
Text
If a column contains text and you want to select cells containing particular text, the Filter() function can be used. In the following example, the template file contains a list of countries, and rows are selected that contain a particular country name. Sample files are given below.
Blanks
If a column contains text but some cells are blank, and you need to filter to select only rows where the cells are blank, the MatchBlanks() function can be used as demonstrated below. Sample files are given below.
Non‑Blank
When cells containing any text are to be filtered, use the MatchNonBlanks() filter function as demonstrated below. Sample files are given below.
Custom filter with Contains
Excel provides custom filters, such as filtering rows that contain a specific string. This feature is available in Aspose.Cells and is demonstrated below by filtering the names in the sample file. Sample files are given below.
Custom filter with NotContains
Excel provides custom filters, such as filtering rows that do not contain a specific string. This feature is available in Aspose.Cells and is demonstrated below by filtering the names in the sample file. Sample file is given below.
Custom filter with BeginsWith
Excel provides custom filters, such as filtering rows that begin with a specific string. This feature is available in Aspose.Cells and is demonstrated below by filtering the names in the sample file. Sample file is given below.
Custom filter with EndsWith
Excel provides custom filters, such as filtering rows that end with a specific string. This feature is available in Aspose.Cells and is demonstrated below by filtering the names in the sample file. Sample file is given below.