The DataFilter control supports five different kinds of filters namely, BoolFilter, RangeFilter, DateRangeFilter, ChecklistFilter and CalendarFilter, to filter different types of data. Corresponding to each filter, an accordion tab is added to the DataFilter control which contains the controls used to filter the data-aware control by a specific field. For example, 

• BoolFilter - The DataFilter control generates a BoolFilter for a boolean data field, which is represented by a checkbox.
• RangeFilter - The DataFilter control generates a RangeFilter for a numeric data field, which provides range editors and a range slider to filter values in the specified range.
• DateRangeFilter - The DataFilter control generates a DateRangeFilter for a DateTime type of data field, which provides range editors and a range slider to filter values in the specified date range.
• ChecklistFilter - This filter is autogenerated for textual data. But it can also be used for any other data type. For example, if you need to allow selecting among several numeric values, CheckListFilter is a better option than RangeFilter.
• CalendarFilter - The filter can be used for a DateTime type of data field and is represented by a calendar to filter dates.

When the AutoGenerateFilters property of the C1DataFilter class is set to true, filters are automatically generated depending on the type of the fields present in the DataSource. These filters are added to the FilterCollection and can be accessed using Filters property of the C1DataFilter class.

The following code demonstrates how filters can be automatically generated in the DataFilter control.

'Setting AutoGenerateFilters to true generates the filters automatically. 
c1DataFilter1.AutoGenerateFilters = true
c1DataFilter1.DataSource = _table
c1DataFilter1.ShowToolTips = true

//Setting AutoGenerateFilters to true generates the filters automatically. 
c1DataFilter1.AutoGenerateFilters = true; 
c1DataFilter1.DataSource = _table;
c1DataFilter1.ShowToolTips = true;

To add filters programmatically to the DataFilter control, follow these steps:

1. Create an instance of one of the different filter types, namely BoolFilter, RangeFilter, ChecklistFilter or DateRangeFilter. The instance accepts a parameter that is the name of the data field for which the filter is being defined.
2. Specify the important properties related to the filter class.
3. Finally, add the filter instance to the FilterCollection.

To add a RangeFilter to the DataFilter control, use the following code. This code sets the header, editor type, editor width, tooltip, maximum value, and minimum value for the range filter.

'Add RangeFilter
Dim rangeFilter As RangeFilter = New RangeFilter("UnitPrice")
        
'Set text for the header
rangeFilter.HeaderText = "Unit Price"
        
'Set minimum and maximum values for the RangeFilter
rangeFilter.Minimum = 0
rangeFilter.Maximum = 100
        
'Specify the type of editor
rangeFilter.EditorsType = C1.DataFilter.EditorsType.SpinEditor
        
'Show the editor
rangeFilter.EditorsVisible = true
        
'Set the width of editor
rangeFilter.EditorWidth = 50
        
'Sets text of the ToolTip to appear on the filter header
rangeFilter.ToolTip = "Select the price range to perform " +
                      "filtering on the grid"
        
'Add filter to the DataFilter control
c1DataFilter1.Filters.Add(rangeFilter)

//Add RangeFilter
RangeFilter rangeFilter = new RangeFilter("UnitPrice");

//Set text for the header
rangeFilter.HeaderText = "Unit Price";

//Set minimum and maximum values for the RangeFilter
rangeFilter.Minimum = 0;
rangeFilter.Maximum = 100;

//Specify the type of editor
rangeFilter.EditorsType = C1.DataFilter.EditorsType.SpinEditor;

//Show the editor
rangeFilter.EditorsVisible = true;
            
//Set the width of editor
rangeFilter.EditorWidth = 50;

//Sets text of the ToolTip to appear on the filter header
rangeFilter.ToolTip = "Select the price range to perform " + "filtering on the grid";

//Add filter to the DataFilter control
c1DataFilter1.Filters.Add(rangeFilter);

Reset Filters

DataFilter also supports filter reset feature. This enables you to the reset the filter selection to its default value on the click of a button. You can use reset method to implement this feature on the filters. 

As shown in the GIF below, all the filter selections are cleared after clicking on the reset filter button.

 To implement this feature, you can use the following code. In this code, reset method is applied on the brand filter.

//Reset the ChecklistFilter created for brand field. 
private void resetbtn_Click(object sender, EventArgs e)
        {
            brandFilter.Reset();
        }