//指定表名读出成一个FeatureSource
public FeatureSource ReadFromTable(string table)
{
string connStr = "Server=" + server + ";Port=" + port + ";UserId=" + user + ";Password="******";Database=" + database + ";";
try
{
//获得图层类型和参考坐标系
Dictionary <string, string> dt1 = GetSchemePara(table);
OSGeo.OGR.wkbGeometryType geometryType = String2Type.String2wkbGeometryType(dt1["type"]);
ReferenceSystem rs = new SRS(new OSGeo.OSR.SpatialReference(Int2SRText(int.Parse(dt1["srid"]))));
NpgsqlConnection conn = new NpgsqlConnection(connStr);
conn.Open();
IDbCommand dbcmd = conn.CreateCommand();
dbcmd.CommandText = "SELECT *,ST_AsText(geom) AS geom1 FROM \"" + table + "\"";
IDataReader dr = dbcmd.ExecuteReader();
Dictionary <string, OSGeo.OGR.FieldDefn> fields = new Dictionary <string, OSGeo.OGR.FieldDefn>();
string[] fieldNames = new string[dr.FieldCount - 2];
for (int i = 0; i < dr.FieldCount - 2; i++)
{
OSGeo.OGR.FieldDefn d = GetFieldDefn(dr.GetName(i), dr.GetDataTypeName(i));
fields.Add(dr.GetName(i), d);
fieldNames[i] = dr.GetName(i);
}
Schema schema = new Schema(table, geometryType, rs, fields);
List <Feature> flst = new List <Feature>();
while (dr.Read())
{
int featureID = int.Parse(dr[0].ToString());
Geometry.Geometry geometry = WKT2Feature.WKT2Geometry(dr[dr.FieldCount - 1].ToString());
Dictionary <string, Object> attributes = new Dictionary <string, object>();
for (int i = 0; i < dr.FieldCount - 2; i++)
{
Object o;
switch (fields[fieldNames[i]].GetFieldType())
{
case OSGeo.OGR.FieldType.OFTInteger:
o = int.Parse(dr[i].ToString());
break;
case OSGeo.OGR.FieldType.OFTReal:
o = double.Parse(dr[i].ToString());
break;
default:
o = dr[i].ToString();
break;
}
attributes.Add(fieldNames[i], o);
}
Feature feature = new Feature(featureID, schema, geometry, attributes);
flst.Add(feature);
}
FeatureCollection fc = new FeatureCollection(flst);
FeatureSource fs = new FeatureSource(schema, fc);
return(fs);
conn.Close();
}
catch (Exception e)
{
return(null);
}
}
public OSGeo.OGR.FieldDefn GetFieldDefn(string fieldName, string type)
{
return(new OSGeo.OGR.FieldDefn(fieldName, String2Type.String2OGRFiledType(type)));
}
