File listing

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ESRI Shapefiles (SHP)

Also known as ESRI ArcView. ESRI is the company that introduced this format; ArcView was the first product to use shapefiles.

Shapefiles are made up of a minimum of three similarly named files, with different suffixes:

Countries_area.dbf
Countries_area.shp
Countries_area.shx

Data access/connection method

  • Shapefile access is built directly into MapServer. It is also available through OGR, but direct access without OGR is recommended and discussed here.

  • The path to the shapefile is required. No file extension should be specified.

  • Shapefiles hold only one layer of data, therefore no distinction needs to be made.

ogrinfo examples

  • The directory can serve as a data source.

  • Each shapefile in a directory serves as a layer.

  • A shapefile can also be a data source. In this case the layer has the same prefix as the shapefile.

Here's an example that uses ogrinfo on a directory with multiple shapefiles:

     > ogrinfo /data/shapefiles/     INFO: Open of '/data/shapefiles/'     using driver 'ESRI Shapefile' successful.     1: wpg_h2o (Line String)     2: wpg_roads (Line String)     3: wpg_roads_dis (Line String)     4: wpgrestaurants (Point) 

Here's an example that uses ogrinfo on a single shapefile:

     > ogrinfo /data/shapefiles/Countries_area.shp     Had to open data source read-only.     INFO: Open of 'Countries_area.shp'     using driver 'ESRI Shapefile' successful.     1: Countries_area (Polygon) 

Here's an example that uses ogrinfo to examine the structure of the file/layer:

     > ogrinfo -summary /data/shapefiles/Countries_area.shp Countries_area     Had to open data source read-only.     INFO: Open of 'Countries_area.shp'     using driver 'ESRI Shapefile' successful.           Layer name: Countries_area     Geometry: Polygon     Feature Count: 27458     Extent: (-180.000000, -90.000000) - (180.000000, 83.627419)     Layer SRS WKT:     (unknown)     FAC_ID: Integer (5.0)     TILE: Integer (3.0)     ARCLIST: String (254.0)     NAM: String (77.0)     PERIMETER: Real (22.17)     POLYGONCOU: Integer (6.0)     NA2DESC: String (45.0) 

Map file example

     LAYER       NAME my_shapefile       TYPE POLYGON       DATA countries_area       STATUS OFF       CLASS         NAME "Countries"         OUTLINECOLOR 0 0 0       END     END 

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    Web Mapping
    Web Mapping Illustrated: Using Open Source GIS Toolkits
    ISBN: 0596008651
    EAN: 2147483647
    Year: 2005
    Pages: 138

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