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 SimpleAttributeOperand , AttributeOperand , LiteralOperand or ElementOperand .

operatorType : enumeration

The filter operator.

Possible operators for a FilterElement that are specified in OPC UA 1.05 part 4, 7.7.3

常量
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 .