DxFilterBuilderField.IsCollection Property

Specifies whether the field stores object collections.

Namespace: DevExpress.Blazor

Assembly: DevExpress.Blazor.v25.2.dll

NuGet Package: DevExpress.Blazor

Declaration

[DefaultValue(false)]
[Parameter]
public bool IsCollection { get; set; }

Property Value

Type	Default	Description
Boolean	false	true if the field stores object collections; otherwise, false.

Remarks

Enable the IsCollection property to define a collection field. Such field stores an object collection and supports aggregate operators (functions). Aggregate functions calculate collection summaries and allow users to create filter conditions based on the aggregated results. For example, users can filter out invoices containing fewer than 5 items in the Products field.

The following aggregate functions are available:

Exists

Returns true if the collection contains at least one field (object).

Count

Calculates the number of fields (objects) in the collection.

Avg

Calculates the average of all values in the collection.

Sum

Calculates the total sum of all values in the collection.

Min

Returns the minimum value in the collection.

Max

Returns the maximum value in the collection.

For more information about available operators in Blazor Filter Builder, refer to the following article: Filter Operators in Blazor Filter Builder.

Note

For a collection field, the Filter Builder automatically sets its Type property to @typeof(List<object>) and hides the nested hierarchy in the UI.

The following code snippet defines an Orders collection field:

<DxFilterBuilder @bind-FilterCriteria="FilterCriteria">
    <Fields>
        <DxFilterBuilderField FieldName="ProductName" Caption="Product" Type="@typeof(string)" />
        <DxFilterBuilderField FieldName="UnitPrice" Caption="Unit Price" Type="@typeof(decimal)" />
        <DxFilterBuilderField FieldName="UnitsInStock" Caption="Units In Stock" Type="@typeof(int)" />
        <DxFilterBuilderField FieldName="Orders" Caption="Orders" IsCollection="true">
            <Fields>
                <DxFilterBuilderField FieldName="OrderDate" Caption="Order Date" Type="@typeof(DateTime?)" />
                <DxFilterBuilderField FieldName="CustomerName" Caption="Customer" Type="@typeof(string)" />
                <DxFilterBuilderField FieldName="Quantity" Caption="Quantity" Type="@typeof(int)" />
            </Fields>
        </DxFilterBuilderField>
    </Fields>
</DxFilterBuilder>

Run Demo: Filter Builder - Collection Fields and Aggregate Operators