How to read the current scale of a Map?

Question

Hi Everybody:

I am writing a Silverlight program that reads a ArcGIS Server 10 map service feature layer (such as http://sampleserver3.arcgisonline.com/ArcGIS/rest/services/Network/USA/MapServer/80).
    When this layer is displayed on the map I want to find a method to read the current display scale, because I want to zoom out to make sure the scale number is larger than "Min. Scale" of the map service, and then I can check whether the map is displayed when the scale is out of the range defined by "Min. Scale" and "Max. Scale".
    However, I haven't found the method to get the exact number. The Scalebar control give a good scale legend, but not the exact number to compare with "Min. Scale" of the map service. In the Map control I haven't found a property to return that value neither.
    Any idea how I can get the nubmer?
    Thank you.

My development environment:
-- .NET 4
-- C# and Visual Studio 2010
-- Silverlight 4
-- ESRI ArcGIS API for Microsoft Silverlight/WPF
-- ArcGIS server 10.01 map services

vipulsoni · Answer

Thank you jenniferdnery! I will try. Take this code.. might help you. #region getMapScale ///

/// getMapScale ///

/// /// public double getMapScale(Map esriMap) { double dpi = 96; //screen resolution: pixels per inch double screenUnitsPerMapUnit = 39.37; //inches per meter double mapResolution = esriMap.Resolution; double scale = (dpi * screenUnitsPerMapUnit * mapResolution); return scale; } #endregion #region MAP SCALE CHANGE ///

/// MAP SCALE CHANGED ///

/// /// private void Map_ExtentChanged(object sender, ExtentEventArgs e) { double Map_Scale = getMapScale(Map); int scaled = Convert.ToInt32(Math.Round(Map_Scale)); MapScale.Text = "1 : " + scaled; } #endregion

SuiHuang · Answer

Thank you jenniferdnery! I will try.The ScaleBar has a ScaleValue property: http://help.arcgis.com/en/webapi/silverlight/apiref/ESRI.ArcGIS.Client~ESRI.ArcGIS.Client.ScaleBar~ScaleValue.html which is calculated based on the Map.Resolution.

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JenniferNery · Answer

The ScaleBar has a ScaleValue property: http://help.arcgis.com/en/webapi/silverlight/apiref/ESRI.ArcGIS.Client~ESRI.ArcGIS.Client.ScaleBar~ScaleValue.html which is calculated based on the Map.Resolution.

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