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Create a point, polyline, polygon, or multipoint from the specified OGIS WKB format buffer.
[Visual Basic .NET] Public Sub CreateGeometryFromWkbVariant ( _ ByVal wkb As Object, _ ByRef outGeometry As IGeometry, _ ByRef numBytesRead As Integer _ )
[C#] public void CreateGeometryFromWkbVariant ( object wkb, ref IGeometry outGeometry, ref int numBytesRead );
[C++]
HRESULT CreateGeometryFromWkbVariant(
VARIANT wkb,
IGeometry** outGeometry,
System.Int32* numBytesRead
);
[C++] Parameters wkb
wkb is a parameter of type VARIANT outGeometry [out]
outGeometry is a parameter of type IGeometry** numBytesRead [out]
numBytesRead is a parameter of type long*
private void CreateGeometryFromWkbVariant() { OleDbConnection connection = new OleDbConnection("Provider=ESRI.GeoDB.OLEDB.1;Data Source= C:\\basiceditdatabase.mdb;ExtendedProperties=workspacetype=esriDataSourcesGDB.AccessWorkspaceFactory.1;Geometry=WKB"); //create the command object with the sql query OleDbCommand command = new OleDbCommand("select * from line_edit", connection); try { connection.Open(); //create the datareader object to connect to table OleDbDataReader reader = command.ExecuteReader(); //Iterate through the geodatabase and add new Geometries to to GeometryBag IGeometryFactory2 factory = new GeometryEnvironmentClass(); IGeometryCollection geometryCollection = new GeometryBagClass(); IGeometry outGeometry; int bytesRead; object missing = Type.Missing; while (reader.Read()) { int shapeColumn = reader.GetOrdinal("SHAPE"); object byteArrayObject = reader.GetValue(shapeColumn); //Re-create the geometry from the WKB data factory.CreateGeometryFromWkbVariant(byteArrayObject, out outGeometry, out bytesRead); if(outGeometry!= null) { //add the geometry to the geometryColection's end geometryCollection.AddGeometry(outGeometry, ref missing, ref missing); } } //don't forget to clean up reader.Close(); connection.Close(); System.Windows.Forms.MessageBox.Show(geometryCollection.GeometryCount + " geomtries added"); } //Some usual exception handling catch (OleDbException e) { System.Windows.Forms.MessageBox.Show("Error: {0}", e.Errors[0].Message); } }
Dim pGFact As ESRI.ArcGIS.Geometry.IGeometryFactory
Dim pGeoEnv As ESRI.ArcGIS.Geometry.GeometryEnvironment
Dim pGeomCol As ESRI.ArcGIS.Geometry.IGeometryCollection
Dim pGeom As ESRI.ArcGIS.Geometry.IGeometry
Dim cBytesread As Long
Dim pEnvelope As ESRI.ArcGIS.Geometry.IEnvelope
Dim adors As ADODB.Recordset
Dim adocon As ADODB.Connection
Dim sConstring As String, sSQLstring As String
Dim WKBData As Object
pGeoEnv = New ESRI.ArcGIS.Geometry.GeometryEnvironment
pEnvelope = New ESRI.ArcGIS.Geometry.Envelope
pGFact = pGeoEnv
adors = New ADODB.Recordset
adocon = New ADODB.Connection
sConstring = "Provider=ESRI.GeoDB.OLEDB.1;" & "Data Source= d:\temp\us_states.mdb;" & "ExtendedProperties=workspacetype=esriDataSourcesGDB.AccessWorkspaceFactory.1;Geometry=WKB"
sSQLstring = "select * from us_states"
adocon.Open(sConstring)
adors.Open(sSQLstring, adocon, ADODB.CursorTypeEnum.adOpenForwardOnly, ADODB.LockTypeEnum.adLockOptimistic)
Do Until adors.EOF
pGeomCol = New ESRI.ArcGIS.Geometry.GeometryBag
WKBData = adors("Shape").Value
If IsNothing(WKBData) Then
adors.MoveNext()
Else
'++ Re-create the geometry from the WKB data
pGFact.CreateGeometryFromWkbVariant(WKBData, pGeom, cBytesread)
'++ Aggregate the geom envelopes
pEnvelope.Union(pGeom.Envelope)
pGeomCol.AddGeometry(pGeom)
adors.MoveNext()
End If
Loop
IGeometryFactory Interface | IGeometry Interface | IGeometryCollection Interface | IEnvelope Interface