ArcEngine 坐标系转换

/// <summary>

/// 地理坐标系 转 投影坐标系

/// </summary>

/// <param name="x"></param>

/// <param name="y"></param>

/// <param name="GCSType">地理坐标系编号</param>

/// <param name="PRJType">投影坐标系编号</param>

/// <returns></returns>

private IPoint GCStoPRJ(double x, double y, int GCSType, int PRJType)

{

    IPoint pPoint = new PointClass();

    pPoint.PutCoords(x, y);

    ISpatialReferenceFactory pSRF = new SpatialReferenceEnvironmentClass();

    pPoint.SpatialReference = pSRF.CreateGeographicCoordinateSystem(GCSType);

    //GCS_WGS_1984 WKID: 4326 权限: EPSG

    pPoint.Project(pSRF.CreateProjectedCoordinateSystem(PRJType));

    //Xian_1980_3_Degree_GK_CM_114E  WKID: 2383 权限: EPSG

    return pPoint;

}

/// <summary>

/// 投影坐标系 转 地理坐标系

/// </summary>

/// <param name="x"></param>

/// <param name="y"></param>

/// <param name="GCSType">地理坐标系编号</param>

/// <param name="PRJType">投影坐标系编号</param>

/// <returns></returns>

private IPoint PRJtoGCS(double x, double y,int GCSType, int PRJType)

{

    IPoint pPoint = new PointClass();

    pPoint.PutCoords(x, y);

    ISpatialReferenceFactory pSRF = new SpatialReferenceEnvironmentClass();

    pPoint.SpatialReference = pSRF.CreateProjectedCoordinateSystem(PRJType);

    pPoint.Project(pSRF.CreateGeographicCoordinateSystem(GCSType));

    return pPoint;

}