FilterElement QML Type

The OPC UA ContentFilterElement. 更多...

import 语句: import QtOpcUa.
Since: QtOpcUa 5.13

特性

详细描述

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 { ... }
}
					

另请参阅 EventFilter .

特性文档编制

firstOperand : variant

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

operatorType : FilterElement::FilterOperator

The filter operator.

secondOperand : variant

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