本文整理汇总了Python中qgis.core.QgsExpressionContextUtils.createFeatureBasedContext方法的典型用法代码示例。如果您正苦于以下问题：Python QgsExpressionContextUtils.createFeatureBasedContext方法的具体用法？Python QgsExpressionContextUtils.createFeatureBasedContext怎么用？Python QgsExpressionContextUtils.createFeatureBasedContext使用的例子？那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类qgis.core.QgsExpressionContextUtils的用法示例。
在下文中一共展示了QgsExpressionContextUtils.createFeatureBasedContext方法的2个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的Python代码示例。
示例1: test_MatchesTrueForFields
# 需要导入模块: from qgis.core import QgsExpressionContextUtils [as 别名]
# 或者: from qgis.core.QgsExpressionContextUtils import createFeatureBasedContext [as 别名]
def test_MatchesTrueForFields(self):
feature = QgsFeature()
fields = QgsFields()
fields.append(QgsField("testfield", QVariant.Int))
feature.setFields(fields, True)
feature["testfield"] = 20
style = QgsConditionalStyle('"testfield" = @value')
context = QgsExpressionContextUtils.createFeatureBasedContext(feature, fields)
assert style.matches(20, context)示例2: testExpression
# 需要导入模块: from qgis.core import QgsExpressionContextUtils [as 别名]
# 或者: from qgis.core.QgsExpressionContextUtils import createFeatureBasedContext [as 别名]
def testExpression(self, row):
self._errors[row] = None
field = self._mapping[row]
expression = QgsExpression(field['expression'])
if expression.hasParserError():
self._errors[row] = expression.parserErrorString()
return
if self._layer is None:
return
context = QgsExpressionContextUtils.createFeatureBasedContext(QgsFeature(), self._layer.fields())
for feature in self._layer.getFeatures():
context.setFeature(feature)
expression.evaluate(context)
if expression.hasEvalError():
self._errors[row] = expression.evalErrorString()
return
break