Use the Enclose (Polylines to Regions) command to create regions from polygonal areas formed by intersecting polylines. You can form a new region network anyplace where the polylines form an enclosed area. For example, you could create regions from a road net, where the regions are the parcels of land between the roads.
You can also use the Enclose (Polylines to Regions) command with region objects.
This command is modeled after the Combine command, but has two important differences:
- Combine always produces one object, while Enclose (Polylines to Regions) may produce many objects.
- No data aggregation is performed with the Enclose (Polylines to Regions) command.
To use the Enclose (Polylines to Regions) command, your Map window must be active, it must contain an editable layer, and objects in the editable layer must be selected. This is a highway map of the greater New York City metropolitan area. A number of the highways have been selected.
To form regions from the selected polylines:
- In the active Map window, make the layer you want to select from editable.
- Select the objects you want to enclose.
- On the SPATIAL tab, in the Create group, on the Regions list, click Enclose (Polylines to Regions) from the list to open the Create Region Objects from Enclosed Areas dialog box.
- To ignore region objects in the operation, leave the box checked. To include region objects, clear the box. If regions are to be used as input objects, they are automatically converted to polylines for the Enclose (Polylines to Regions) operation.
- Your map displays. The newly formed polygons are selected.
Enclose (Polylines to Regions) preserves the original objects. The selected objects are used as the input objects, and the results of the operation are placed in the current editable layer in the active Map window.
When you include regions and other closed objects in the Enclose (Polylines to Regions) command (regions, rectangles, rounded rectangles, and ellipses), the input regions are considered polylines for the purposes of this operation. The regions are converted to polyline objects, and then the Enclose (Polylines to Regions) operation is performed. It is the same as if you were to first convert any closed objects to polyline objects, and then perform the Enclose (Polylines to Regions) operation.
If your selection contains objects that are not linear and are not closed (for example, points, multipoints, collections or text objects), you will get an error. If the selection contains closed objects, and the Ignore Region Objects check box is selected, then these closed objects will be ignored.