Map Zoom

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Map zoom is a feature of the Nevron map importer that lets you zoom the map to a one or more specific elements. To set the map zoom you can use the MapZoom property of the map importer. Nevron Map for .NET currently supports the following map zoom types:

NMapZoomToAllLayers - zooms the map to all map layers added to the map importer. This is the default value of the MapZoom property of the map importer.
NMapZoomToLayer - zooms the map to a specific map layer.
NMapZoomToDataBoundFeatures - zooms the map to all data bound features.
NMapZoomToFeatures - zooms a map to a set of map features, which match a given filter.

Zooming to a Set of Map Features

To zoom a map to a set of map features, you should create an NMapZoomToFeatures filter by passing an NMapFeatureFilter to its constructor. If you want to filter map features based on the value of one or more of their attributes, you should use the NMapFeatureAttributesFilter. It is similar to CSS selectors and accepts two types of selector parts - conditions and combinators (OR and AND). The Add method of the filter adds a condition and an AND combinator after it by default. You can use its 2 parameter overload to specify a combinator explicitely.

The following code example demonstrates how to create and configure a map zoom to features object:

Zoom to map features	Copy Code
NMapShapeFieldsFilter filter = new NMapFeatureAttributesFilter(); filter.Add(new NMapShapeFilterCondition("Sales", MapConditionOperator.Equals, 67), NMapShapeFilterCombinator.Or); filter.Add(new NMapShapeFilterCondition("Sales", MapConditionOperator.GreaterThan, 106)); filter.Add(new NMapShapeFilterCondition("Sales", MapConditionOperator.LessThan, 107)); mapImporter.MapZoom = new NMapZoomToFeatures(filter);

Zoom to map features

Copy Code

NMapShapeFieldsFilter filter = new NMapFeatureAttributesFilter();
filter.Add(new NMapShapeFilterCondition("Sales", MapConditionOperator.Equals, 67), NMapShapeFilterCombinator.Or);
filter.Add(new NMapShapeFilterCondition("Sales", MapConditionOperator.GreaterThan, 106));
filter.Add(new NMapShapeFilterCondition("Sales", MapConditionOperator.LessThan, 107));

mapImporter.MapZoom = new NMapZoomToFeatures(filter);

This map zoom object zooms the map to all map features whose "Sales" attribute value is equal to 67 or is between 106 and 107.