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IDisplayTransformation.ScaleRatio Property (ArcObjects .NET 10.7 SDK)
ArcObjects Help for .NET developers > ArcObjects Help for .NET developers > ArcObjects namespaces > Display > ESRI.ArcGIS.Display > Interfaces > ID > IDisplayTransformation Interface > IDisplayTransformation.ScaleRatio Property
ArcGIS Developer Help

IDisplayTransformation.ScaleRatio Property

Scale between FittedBounds and DeviceFrame.

[Visual Basic .NET]
Public Property ScaleRatio As Double
public double ScaleRatio {get; set;}
HRESULT get_ScaleRatio(
  System.Double* scale
HRESULT put_ScaleRatio(
  double scale
scale [out, retval]

scale is a parameter of type double* scale [in]
scale is a parameter of type double

Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.


Several objects that manage a DisplayTransformation, such as the Map object, use this property to control the map scale.  Map scale is the relationship between the dimensions of features on a map and the geographic objects they represent on the earth, commonly expressed as a fraction or a ratio.  A map scale of 1/100,000 or 1:100,000 means that one unit of measure on the map equals 100,000 of the same units on the earth. When you zoom in or out in ArcMap's data view, you are changing this property on the Map's DisplayTransformation .

The Map object has a short-cut (IMap::MapScale) directly to this property on its DisplayTransformation object.

The PageLayout object does not use this property the same way as the Map object.  In ArcMap's layout view, zooming in is akin to using a magnifying glass to zoom in on the page where the map is displayed.  When you zoom in, you are magnifying what is actually going to print.  To get this effect, the PageLayout objects always keeps its ReferenceScale set to zero and its ScaleRatio set to 1:1 (meaning that 1 inch on the screen equals one inch on the printer).

See Also

IDisplayTransformation Interface