FilterElement QML Type | Qt OPC UA 6.4.1

- Qt 6.4
- Qt OPC UA
- QML Types
- FilterElement
- Qt 6.4.1 Reference Documentation

# FilterElement QML Type

The OPC UA ContentFilterElement. More...

Import Statement: | import QtOpcUa
Since: | QtOpcUa 5.13

- List of all members, including inherited members

## Properties

- firstOperand : variant
- operatorType : enumeration
- secondOperand : variant

## Detailed Description

A content filter element contains an operator and operands. There are four different operator types which contain literal values, references to attributes of nodes or to other content filter elements.

A combination of one or more content filter elements makes a content filter which is used by the server to filter data for the criteria defined by the content filter elements. For example, the `where` clause of an event filter is a content filter which is used to decide if a notification is generated for an event.

     QtOpcUa.FilterElement {
         operator: QtOpcUa.FilterElement.GreaterThanOrEqual
         firstOperand: QtOpcUa.SimpleAttributeOperand { ... }
         secondOperand: QtOpcUa.LiteralOperand { ... }
     }

See also EventFilter.

## Property Documentation

firstOperand : variant

First operand to be used with the operator. This can be one of SimpleAttributeOperand, AttributeOperand, LiteralOperand or ElementOperand.

operatorType : enumeration

The filter operator.

Possible operators for a FilterElement that are specified in OPC-UA part 4, Tables 115 and 116.

Constant | Value
--- | ---
`FilterElement.Equals`
`FilterElement.IsNull`
`FilterElement.GreaterThan`
`FilterElement.LessThan`
`FilterElement.GreaterThanOrEqual`
`FilterElement.LessThanOrEqual`
`FilterElement.Like`
`FilterElement.Not`
`FilterElement.Between`
`FilterElement.InList`
`FilterElement.And`
`FilterElement.Or`
`FilterElement.Cast`
`FilterElement.InView`
`FilterElement.OfType`
`FilterElement.RelatedTo`
`FilterElement.BitwiseAnd`
`FilterElement.BitwiseOr`

secondOperand : variant

Second operand to be used with the operator. This can be one of SimpleAttributeOperand, AttributeOperand, LiteralOperand or ElementOperand.