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IDisplayTransformation.ZoomResolution 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.ZoomResolution Property
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IDisplayTransformation.ZoomResolution Property

Indicates if resolution is tied to visible bounds. If true, zooming in magnifies contents (i.e., zoom in on page).

[Visual Basic .NET]
Public Property ZoomResolution As Boolean
public bool ZoomResolution {get; set;}
HRESULT get_ZoomResolution(
HRESULT put_ZoomResolution(
  Boolean* flag
flag [in]

flag is a parameter of type bool flag [out, retval]
flag is a parameter of type bool*

Product Availability

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


ZoomResolution is a flag that tells the DisplayTransformation whether or not to automatically adjust the device resolution (pixels per inch) based on the current zoom level.  This is useful when you want to define a page display.  With this kind of display, graphics are drawn at their actual size, i.e., scale is 1:1.  Zooming in really means magnifying the graphics when drawing them to a computer monitor.  When a map page is exported or printed, the zoom level is always 100% and the extent is defined by the page.  Use ZoomResolution to specify this page-style behavior.  With ZoomResolution set to true, the DisplayTransformation monitors the current zoom level.  When the display is zoomed to 100%, a higher effective resolution is calculated.  This has the effect of automatically magnifying all drawing.  The Resolution property always returns the effective resolution.  ScaleRatio always returns 1:1.

Note, when ZoomResolution is true, in order to get the physical device resolution, you must temporarily set ZoomResolution to false, get the Resolution, and then restore the ZoomResolution to true.

To find the current zoom percentage, simply divide the effective resolution by the physical resolution and multiply by 100.  This is what IPageLayout::ZoomPercent does.

If you don't want graphics to scale as you zoom in, set this flag to false.  For example, the Map object sets its DisplayTransformation's ZoomResolution property to false so that the contents of the map are not magnified when you zoom in on them.  The PageLayout sets its DisplayTransformaion's ZoomResolution property to true.

See Also

IDisplayTransformation Interface | IDisplayTransformation.ZoomResolution Property | IDisplayTransformation.Resolution Property