ShapefileWriter.SplitBigFiles Property
Gets a flag controlling whether big files will be split.
Syntax
public System.Boolean SplitBigFiles { get; }Property Value
Default: false
A flag controlling whether big files will be split.
Remarks
The files for Shapefile data have size limits: according to Esri, both the .shp file and the .dbf file are limited to 2 GB. These limits are not forced by the formats, though: a .dbf file can be much larger, and the .shp format specification would allow files up to 4 GB, or up to 8 GB with a modest reinterpretation (using unsigned integers instead of signed ones for offsets and file size). So, some GIS system can handle huge .dbf files as well as .shp files up to 4 or 8 GB, but for best interoperability, one should avoid creating files larger than 2 GB.
If SplitBigFiles is False, the WriteFeature method will throw an exception if the .shp file or the .dbf file would exceed 2 GB.
If SplitBigFiles is True, the WriteFeature method will automatically split the result into multiple files, to avoid creating .shp and .dbf files larger than 2 GB. For example, let us say the writer FileName is roads.shp. Then the WriteFeature method will start by writing into a file of that name and its auxiliary files:
roads.shp roads.shx roads.dbf roads.cpg roads.prj
However, if the write method determines that writing a feature would make roads.shp or roads.dbf exceed 2 GB, it will close the files, rename them by adding a _0 suffix:
roads_0.shp roads_0.shx roads_0.dbf roads_0.cpg roads_0.prj
and start on a new set of files with a _1 suffix:
roads_1.shp roads_1.shx roads_1.dbf roads_1.cpg roads_1.prj
Then, if roads_1.shp or roads_1.dbf later reaches 2 GB, the _1 files will be closed and the writer will start on a new set of files with a _2 suffix, etc.
It is possible to read the multiple shapefiles with one ShapefileDataSet by using an asterisk as a wildcard in the ShapefileDataSet.fileName property. In this example, a dataset file name of
roads*.shp
would match a single file roads.shp as well as multiple files roads_0.shp, roads_1.shp, roads_2.shp... But note that the wildcard file name may also match some unintended file in the folder, for example a file named roadsigns.shp in this case.
Of course, in many cases it may be better to use application logic to split the data in some other way, for example by geographic region.
Platforms
Windows, Linux, Android