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Python QgsVirtualLayerDefinition.setGeometrySrid方法代码示例

本文整理汇总了Python中qgis.core.QgsVirtualLayerDefinition.setGeometrySrid方法的典型用法代码示例。如果您正苦于以下问题:Python QgsVirtualLayerDefinition.setGeometrySrid方法的具体用法?Python QgsVirtualLayerDefinition.setGeometrySrid怎么用?Python QgsVirtualLayerDefinition.setGeometrySrid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qgis.core.QgsVirtualLayerDefinition的用法示例。


在下文中一共展示了QgsVirtualLayerDefinition.setGeometrySrid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: processAlgorithm

# 需要导入模块: from qgis.core import QgsVirtualLayerDefinition [as 别名]
# 或者: from qgis.core.QgsVirtualLayerDefinition import setGeometrySrid [as 别名]
    def processAlgorithm(self, feedback):
        layers = self.getParameterValue(self.INPUT_DATASOURCES)
        query = self.getParameterValue(self.INPUT_QUERY)
        uid_field = self.getParameterValue(self.INPUT_UID_FIELD)
        geometry_field = self.getParameterValue(self.INPUT_GEOMETRY_FIELD)
        geometry_type = self.getParameterValue(self.INPUT_GEOMETRY_TYPE)
        geometry_crs = self.getParameterValue(self.INPUT_GEOMETRY_CRS)

        df = QgsVirtualLayerDefinition()
        layerIdx = 1
        if layers:
            for layerSource in layers.split(';'):
                layer = dataobjects.getObjectFromUri(layerSource)
                if layer:
                    df.addSource('input{}'.format(layerIdx), layer.id())
                layerIdx += 1

        if query == '':
            raise GeoAlgorithmExecutionException(
                self.tr('Empty SQL. Please enter valid SQL expression and try again.'))
        else:
            df.setQuery(query)

        if uid_field:
            df.setUid(uid_field)

        if geometry_type == 1:  # no geometry
            df.setGeometryWkbType(QgsWkbTypes.NullGeometry)
        else:
            if geometry_field:
                df.setGeometryField(geometry_field)
            if geometry_type > 1:
                df.setGeometryWkbType(geometry_type - 1)
            if geometry_crs:
                crs = QgsCoordinateReferenceSystem(geometry_crs)
                if crs.isValid():
                    df.setGeometrySrid(crs.postgisSrid())

        vLayer = QgsVectorLayer(df.toString(), "temp_vlayer", "virtual")
        if not vLayer.isValid():
            raise GeoAlgorithmExecutionException(vLayer.dataProvider().error().message())

        writer = self.getOutputFromName(self.OUTPUT_LAYER).getVectorWriter(
            vLayer.fields().toList(),
            # Create a point layer (without any points) if 'no geometry' is chosen
            vLayer.wkbType() if geometry_type != 1 else 1,
            vLayer.crs())

        features = vector.features(vLayer)
        total = 100.0 / len(features)
        outFeat = QgsFeature()
        for current, inFeat in enumerate(features):
            outFeat.setAttributes(inFeat.attributes())
            if geometry_type != 1:
                outFeat.setGeometry(inFeat.geometry())
            writer.addFeature(outFeat)
            feedback.setProgress(int(current * total))
        del writer
开发者ID:wongjimsan,项目名称:QGIS,代码行数:60,代码来源:ExecuteSQL.py

示例2: processAlgorithm

# 需要导入模块: from qgis.core import QgsVirtualLayerDefinition [as 别名]
# 或者: from qgis.core.QgsVirtualLayerDefinition import setGeometrySrid [as 别名]
    def processAlgorithm(self, parameters, context, feedback):
        layers = self.parameterAsLayerList(parameters, self.INPUT_DATASOURCES, context)
        query = self.parameterAsString(parameters, self.INPUT_QUERY, context)
        uid_field = self.parameterAsString(parameters, self.INPUT_UID_FIELD, context)
        geometry_field = self.parameterAsString(parameters, self.INPUT_GEOMETRY_FIELD, context)
        geometry_type = self.parameterAsEnum(parameters, self.INPUT_GEOMETRY_TYPE, context)
        geometry_crs = self.parameterAsCrs(parameters, self.INPUT_GEOMETRY_CRS, context)

        df = QgsVirtualLayerDefinition()
        for layerIdx, layer in enumerate(layers):
            df.addSource('input{}'.format(layerIdx + 1), layer.id())

        if query == '':
            raise QgsProcessingException(
                self.tr('Empty SQL. Please enter valid SQL expression and try again.'))
        else:
            localContext = self.createExpressionContext(parameters, context)
            expandedQuery = QgsExpression.replaceExpressionText(query, localContext)
            df.setQuery(expandedQuery)

        if uid_field:
            df.setUid(uid_field)

        if geometry_type == 1:  # no geometry
            df.setGeometryWkbType(QgsWkbTypes.NoGeometry)
        else:
            if geometry_field:
                df.setGeometryField(geometry_field)
            if geometry_type > 1:
                df.setGeometryWkbType(geometry_type - 1)
            if geometry_crs.isValid():
                df.setGeometrySrid(geometry_crs.postgisSrid())

        vLayer = QgsVectorLayer(df.toString(), "temp_vlayer", "virtual")
        if not vLayer.isValid():
            raise QgsProcessingException(vLayer.dataProvider().error().message())

        (sink, dest_id) = self.parameterAsSink(parameters, self.OUTPUT, context,
                                               vLayer.fields(), vLayer.wkbType() if geometry_type != 1 else 1, vLayer.crs())
        if sink is None:
            raise QgsProcessingException(self.invalidSinkError(parameters, self.OUTPUT))

        features = vLayer.getFeatures()
        total = 100.0 / vLayer.featureCount() if vLayer.featureCount() else 0
        for current, inFeat in enumerate(features):
            if feedback.isCanceled():
                break

            sink.addFeature(inFeat, QgsFeatureSink.FastInsert)
            feedback.setProgress(int(current * total))
        return {self.OUTPUT: dest_id}
开发者ID:lynxlynxlynx,项目名称:Quantum-GIS,代码行数:53,代码来源:ExecuteSQL.py


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