// 地図のEPSGが2451の場合

地図座標をピクセルに変換
[code]
ESRI.ArcGIS.Geometry.IPoint pt = new ESRI.ArcGIS.Geometry.Point();
pt.PutCoords(-35708, -53655);
ESRI.ArcGIS.Display.IScreenDisplay screenDisplay = axMapControl1.ActiveView.ScreenDisplay;
int x;
int y;
screenDisplay.DisplayTransformation.FromMapPoint(pt, out x, out y);
[/code]

ピクセルを地図座標に変換

[code]
ESRI.ArcGIS.Display.IScreenDisplay screenDisplay = axMapControl1.ActiveView.ScreenDisplay;
ESRI.ArcGIS.Geometry.IPoint point = screenDisplay.DisplayTransformation.ToMapPoint(100, 100);
[/code]