How to import or export a spatial reference

Importing or exporting a spatial reference

private void ImportExportSR_Example()
{
    // Set up the SpatialReferenceEnvironment.
    // SpatialReferenceEnvironment is a singleton object and needs to use the Activator class.
    Type factoryType=Type.GetTypeFromProgID(
        "esriGeometry.SpatialReferenceEnvironment");
    System.Object obj=Activator.CreateInstance(factoryType);
    ISpatialReferenceFactory3 spatialReferenceFactory=obj as
        ISpatialReferenceFactory3;

    // Create a predefined PCS and set its coordinate grid information.
    // The default XY tolerance value is 0.001 meters or its equivalent in the coordinate 
    // system units.
    IProjectedCoordinateSystem projectedCoordinateSystem =
        spatialReferenceFactory.CreateProjectedCoordinateSystem((int)
        esriSRProjCSType.esriSRProjCS_WGS1984UTM_10N);
    ISpatialReferenceResolution spatialReferenceResolution =
        projectedCoordinateSystem as ISpatialReferenceResolution;
    ISpatialReferenceTolerance spatialReferenceTolerance=projectedCoordinateSystem
        as ISpatialReferenceTolerance;

    spatialReferenceResolution.ConstructFromHorizon();
    spatialReferenceTolerance.SetDefaultXYTolerance();

    // Export the PCS to a .prj file.
    String fileName="c:\\temp\\utm10.prj";
    spatialReferenceFactory.ExportESRISpatialReferenceToPRJFile(fileName,
        projectedCoordinateSystem);

    // Rehydrate it as a new spatial reference object.
    ISpatialReference projectedCoordinateSystem2 =
        spatialReferenceFactory.CreateESRISpatialReferenceFromPRJFile(fileName);

    // See if they are equal.
    IClone comparison=projectedCoordinateSystem as IClone;

    // Should be true, but coordinate grid information has not been checked.
    System.Windows.Forms.MessageBox.Show((comparison.IsEqual
        (projectedCoordinateSystem2 as IClone)).ToString());

    ISpatialReference2 comparePrecisions=projectedCoordinateSystem as
        ISpatialReference2;

    // Should be false, .prj files do not persist coordinate grid information.
    System.Windows.Forms.MessageBox.Show((comparePrecisions.IsXYPrecisionEqual
        (projectedCoordinateSystem2)).ToString());
}

Private Sub ImportExportSR_Example()
    
    ' Set up the SpatialReferenceEnvironment.
    ' SpatialReferenceEnvironment is a singleton object and needs to use the Activator class.
    Dim factoryType As Type=Type.GetTypeFromProgID("esriGeometry.SpatialReferenceEnvironment")
    Dim spatialReferenceFactory As ISpatialReferenceFactory3=CType(Activator.CreateInstance(factoryType), ISpatialReferenceFactory3)
    
    ' Instantiate a predefined coordinate system and set its coordinate grid information.
    Dim projectedCoordinateSystem As IProjectedCoordinateSystem=spatialReferenceFactory.CreateProjectedCoordinateSystem(esriSRProjCSType.esriSRProjCS_WGS1984UTM_10N) '32610
    Dim spatialReferenceResolution As ISpatialReferenceResolution=CType(projectedCoordinateSystem, ISpatialReferenceResolution)
    Dim spatialReferenceTolerance As ISpatialReferenceTolerance=CType(projectedCoordinateSystem, ISpatialReferenceTolerance)
    
    spatialReferenceResolution.ConstructFromHorizon()
    spatialReferenceTolerance.SetDefaultXYTolerance()
    
    ' Export the PCS to a .prj file.
    Dim fileName As String="c:\\temp\\utm10a.prj"
    spatialReferenceFactory.ExportESRISpatialReferenceToPRJFile(fileName, projectedCoordinateSystem)
    
    ' Rehydrate it as a new spatial reference object.
    Dim projectedCoordinateSystem2 As ISpatialReference=spatialReferenceFactory.CreateESRISpatialReferenceFromPRJFile(fileName)
    
    ' See if they are equal.
    Dim comparison As IClone=CType(projectedCoordinateSystem, IClone)
    
    ' Should be true, but coordinate grid information has not been checked.
    System.Windows.Forms.MessageBox.Show((comparison.IsEqual(projectedCoordinateSystem2)).ToString())
    Dim comparePrecisions As ISpatialReference2=CType(projectedCoordinateSystem, ISpatialReference2)
    
    ' Should be false, .prj files do not persist coordinate grid information.
    System.Windows.Forms.MessageBox.Show((comparePrecisions.IsXYPrecisionEqual(projectedCoordinateSystem2)).ToString())
End Sub

See Also:

• ESRI.ArcGIS.Geometry