ContainsOperator Class

An operator which checks if a collection contains at least one object matching a specific criteria.

Namespace: DevExpress.Data.Filtering

Assembly: DevExpress.Data.v23.1.dll

NuGet Package: DevExpress.Data

Declaration

C#

public sealed class ContainsOperator :
    AggregateOperand

VB.NET

Public NotInheritable Class ContainsOperator
    Inherits AggregateOperand

Remarks

The ContainsOperator operator can be used to filter the contents of the XPCollection.

You can also use the CriteriaOperator.Parse method to create a CriteriaOperator operator for a specific expression.

Tip

You can find examples in the following article: Build Criteria - Cheat Sheet.

Examples

Selects Order objects that contain at least one object in their OrderItems collection with the OrderPrice property set to 44.

Expression:

LINQ

// There is no LINQ expression that generates the ContainsOperator you can solve this task using the following expression

CriteriaOperator.FromLambda<Order>(o => o.OrderItems.Any(oi => oi.ItemPrice == 44));

Typed

new ContainsOperator(nameof(Order.OrderItems), new BinaryOperator("ItemPrice", 44));

String

CriteriaOperator.Parse("[OrderItems][ItemPrice = ?]", 44);

Test

Input:

Order	OrderItem	ItemPrice
Order0
	Item0-0	10
	Item0-1	20
Order1
	Item1-0	30
	Item1-1	44

The result:

Order
Order1

---

Selects Orders with Price equal to 99 and has OrderItems with ItemPrice equal to 10:

Expression:

LINQ

CriteriaOperator.FromLambda<Order>(o => o.OrderItems.Any(oi => oi.ItemPrice == 10) && o.Price == 99);

Typed

var containsCriterion = new ContainsOperator(nameof(Order.OrderItems), new BinaryOperator(nameof(OrderItem.ItemPrice), 10));
var simpleCriterion = new BinaryOperator(nameof(Order.Price), 99);
var criterion = new GroupOperator(containsCriterion, simpleCriterion);

String

CriteriaOperator.Parse("[OrderItems][ItemPrice = ?] and Price = ?", 10, 99);

Test

Input:

OrderName	Price	OrderItemName	ItemPrice
Order0	99
		OrderItem00	2
		OrderItem01	4
Order1	99
		OrderItem10	5
		OrderItem11	10

The result:

OrderName
Order1

---

Selects Orders with OrderItems that has Company with CompanyName equal to ‘Company1’:

Expression:

LINQ

CriteriaOperator.FromLambda<Order>(o => o.OrderItems.Any(oi => oi.Company.CompanyName == "Company1"));

Typed

var criterionForCollection = new BinaryOperator("Company.CompanyName", "Company1");
var criterion = new ContainsOperator(nameof(Order.OrderItems), criterionForCollection);

String

CriteriaOperator.Parse("[OrderItems][Company.CompanyName = 'Company1']");

Test

Input:

OrderName	OrderItemName	CompanyName
Order0
	OrderItem00
		Company0
		Company2
Order1
	OrderItem10
		Company1
		Company3

The result:

OrderName
Order1

Inheritance

Object

CriteriaOperator

AggregateOperand

ContainsOperator