Class: QgsExpressionNodeCondition

class qgis.core.QgsExpressionNodeCondition(conditions: Iterable[QgsExpressionNodeCondition.WhenThen], elseExp: QgsExpressionNode = None)

Bases: QgsExpressionNode

Create a new node with the given list of conditions and an optional elseExp expression.

QgsExpressionNodeCondition(QgsExpressionNodeCondition)

An expression node for CASE WHEN clauses.

Parameters
class WhenThen(whenExp: QgsExpressionNode, thenExp: QgsExpressionNode)

Bases: sip.wrapper

A combination of when and then. Simple as that.

Represents a “WHEN… THEN…” portation of a CASE WHEN clause in an expression.

Parameters
clone(self) → QgsExpressionNodeCondition.WhenThen

Gets a deep copy of this WhenThen combination.

Return type

QgsExpressionNodeCondition.WhenThen

thenExp(self) → QgsExpressionNode

The expression node that makes the THEN result part of the condition.

Return type

QgsExpressionNode

Returns

The expression node that makes the THEN result part of the condition.

whenExp(self) → QgsExpressionNode

The expression that makes the WHEN part of the condition.

Return type

QgsExpressionNode

Returns

The expression node that makes the WHEN part of the condition check.

clone(self) → QgsExpressionNode
Return type

QgsExpressionNode

conditions(self) → List[QgsExpressionNodeCondition.WhenThen]

The list of WHEN THEN expression parts of the expression.

Return type

List[QgsExpressionNodeCondition.WhenThen]

Returns

The list of WHEN THEN expression parts of the expression.

dump(self) → str
Return type

str

elseExp(self) → QgsExpressionNode

The ELSE expression used for the condition.

Return type

QgsExpressionNode

Returns

The ELSE expression used for the condition.

evalNode(self, parent: QgsExpression, context: QgsExpressionContext) → Any
Parameters
Return type

Any

isStatic(self, parent: QgsExpression, context: QgsExpressionContext) → bool
Parameters
Return type

bool

needsGeometry(self) → bool
Return type

bool

nodeType(self) → QgsExpressionNode.NodeType
Return type

QgsExpressionNode.NodeType

prepareNode(self, parent: QgsExpression, context: QgsExpressionContext) → bool
Parameters
Return type

bool

referencedColumns(self) → Set[str]
Return type

Set[str]

referencedFunctions(self) → Set[str]
Return type

Set[str]

referencedVariables(self) → Set[str]
Return type

Set[str]