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Introduction - Transferring between ArcView and ARC/INFO

ArcView 3 stores data in a format called the shapefile, which is actually three (or more) files, which all have the same name but different 3-letter extensions (i.e. parcels.shp, parcels.shx, and parcels.dbf). ARC/INFO stores data in coverages, a topology-based data format. ArcView can view coverages but cannot edit them, while ARC/INFO version 7.x and earlier cannot directly work with shapefiles. ArcGIS 8 or 9 (ArcMap) is a completely different software package; although it uses "ArcView" and "ArcInfo" to designate different licensing options, it is a completely different piece of software from its predecessors. ArcGIS 8 and 9 can view and edit shapefiles and view coverages, in addition to other formats including the geodatabase.

The easiest way to transfer an ARC/INFO coverage into ArcView (assuming the coverage is in a place you can access it from ArcView) is to add the coverage as a theme (you have to choose which feature type you want to add) and use the Copy button on the Main Menu dialog (this is the same as Theme-->Convert to Shapefile on the View button bar) to save it as a shapefile. You can also use the ARC command ARCSHAPE to convert a coverage to a shapefile.

To transfer an ArcView shapefile into an ARC/INFO coverage, you need to use the ARC command SHAPEARC. Point and line shapefiles are easy to transfer; just move the shapefile (which is actually 3 or more files-- .shp .shx .dbf and sometimes .sbn and .sbx, etc.) to a directory that ARC can access and type 

Arc: SHAPEARC MYPOINTTHM MYPOINTCOV POINT or
Arc: SHAPEARC MYLINETHM MYLINECOV ARC
Transferring a polygon shape file is a little more complex--the best way to do it seems to be to unbuild the polygon theme into lines and labelpoints using the Unbuild button on the Main Menu dialog (or, better yet, if you built the polygons from lines using this extension, just use the pre-build line shapefile and use the Convert polygons to labelpoints function to create a labelpoint shapefile) and then do the following (MYLINETHM is the line shapefile, MYLABELTHM is the label shapefile): 
Arc: SHAPEARC MYLINETHM MYLINECOV ARC
Arc: SHAPEARC MYLABELTHM MYPOLYCOV POINT
Arc: ARCEDIT
ArcEdit: EDITC MYLINECOV
ArcEdit: EDITF ARC
ArcEdit: SEL ALL
ArcEdit: PUT MYPOLYCOV
ArcEdit: Q
Arc: BUILD MYPOLYCOV POLY
The reason you can't just convert a polygon shapefile directly is that each polygon's perimeter arc will be transferred to the coverage as a line, so there will be two overlapping lines at the common boundary of abutting polygons. This is because of the different way the two file formats store data. If you are an experienced ARC/INFO user, you may know of some way to fix this problem (if you do, email it to me!). You might be able to do this with CLEAN, but this can cause other problems...

There are a few issues you may need to work out with this transfer if you are trying to take an ARC/INFO coverage, turn it into a shapefile, edit it in ArcView, and then convert it back to coverage format.

The coverage format is very complex, and this extension is not intended as a total replacement for ArcEdit. If you want to do ArcEdit tasks using ArcView, you are probably best off just editing one feature (lines, labels, points) at a time in ArcView, using SHAPEARC, and then PUTting the new features into an existing coverage.

Since the release of ArcGIS 8 and 9, fewer people are using coverages and workstation Arc/INFO. ArcGIS 9 has many tools for data conversion and maintaining topology.

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This document was created by DEM/ NWF. Contact: DEM/ NWF.