// 将给定shp转换为Web Mercator投影
public void TransformShp(DataSource ds, string FilePath)
{
Layer layer = ds.GetLayerByIndex(0);
SpatialReference sr = layer.GetSpatialRef();
SpatialReference Mercator = new SpatialReference("");
Mercator.ImportFromEPSG(3857); // Web Mercator
Mercator.SetMercator(0d, 0d, 1d, 0d, 0d);
string strDriver = "ESRI Shapefile";
OSGeo.OGR.Driver oDriver = Ogr.GetDriverByName(strDriver);
oDriver.Register();
//创造新矢量图层
DataSource ds1 = oDriver.CreateDataSource(FilePath, null);
Layer layer1 = ds1.CreateLayer(layer.GetName(), Mercator, layer.GetGeomType(), null);
//读取属性字段名
Feature feature = layer.GetFeature(0);
for (int i = 0; i < feature.GetFieldCount(); i++)
{
FieldDefn fieldDefn = feature.GetFieldDefnRef(i);
layer1.CreateField(fieldDefn, 1);
}
//遍历图层中每个要素
feature = layer.GetNextFeature();
while (feature != null)
{
Geometry geom = feature.GetGeometryRef();
geom.TransformTo(Mercator);
feature.SetGeometry(geom);
layer1.CreateFeature(feature);
feature = layer.GetNextFeature();
}
ds1.FlushCache();
ds1.Dispose();
}
