I use SharpMap for working with shapefile. Now shapefile is big and SharpMap take a long time to loading layers. Please tell me how I can speed up working with shapefile.
My first thought was that you were hitting a drawback of the shapefile format rather than SharpMap but Easy GIS .NET claims to be able to do better than SharpMap with the same format:
The library has been designed to handle very large shapefiles, without compromising performance or memory usage. For example the library is capable of opening shapefiles larger than 1GB and will not crash with OutOfMemoryExceptions like some other libraries. Easy GIS .NET will outperform almost all libraries including DotSpatial, SharpMap and even ESRI ArcObjects. If you have any doubts download the largest shapefile you can find and try and open it with Easy GIS .NET.
I've never used Easy GIS .NET, or SharpMap.
Shapefile is considered a slow format to display in questions like How to improve rendering performance of very large shapefile?