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var arc:ArcGISDynamicMapServiceLayer = new ArcGISDynamicMapServiceLayer(msName.substring(0,msName.lastIndexOf("/")));
var arc:ArcGISDynamicMapServiceLayer = new ArcGISDynamicMapServiceLayer(msName.substring(0,msName.lastIndexOf("/")),FeatureLayer(layer).proxyURL);
var arc:ArcGISDynamicMapServiceLayer = new ArcGISDynamicMapServiceLayer(msName.substring(0,msName.lastIndexOf("/")));
var arc:ArcGISDynamicMapServiceLayer = new ArcGISDynamicMapServiceLayer(msName.substring(0,msName.lastIndexOf("/")),FeatureLayer(layer).proxyURL);