我在ArcGIS中有一个ArcObjects C#工具(大部分代码都在Stack Exchange上找到),用于在用户点击地图中的某个位置时识别地图坐标。这是我使用过的代码:
public override void OnMouseDown(int Button, int Shift, int X, int Y)
{
if (Button == 1)
{
ESRI.ArcGIS.Display.IScreenDisplay screenDisplay = (m_application.Document as IMxDocument).ActiveView.ScreenDisplay;
ESRI.ArcGIS.Geometry.IPoint point = screenDisplay.DisplayTransformation.ToMapPoint(X, Y);
MessageBox.Show("X position is " + point.X.ToString() + " Y position is " + point.Y.ToString());
}
}
我们的地图使用英尺单位,因此工具会显示英尺坐标。我怎样才能让这个工具返回度 - 分 - 秒? ESRI的标准识别工具就是这样做的,也是我希望获得类似结果的工具。
答案 0 :(得分:1)
在获取坐标之前,您可以轻松更改IDisplayTransformation对象的地图单位:
ESRI.ArcGIS.Display.IDisplayTransformation displayTransformation = screenDisplay.DisplayTransformation;
displayTransformation.Units = ESRI.ArcGIS.esriSystem.esriUnits.esriMeters; // or another unit
ESRI.ArcGIS.Geometry.IPoint point = displayTransformation.ToMapPoint(X, Y);
您可以获取有关不同ESRI单位here
的信息答案 1 :(得分:1)
您必须先将屏幕点转换为地图当前坐标系,然后您需要将该点投影到WGS84,然后转换为Degrees Minutes Seconds。我在下面创建了一个类。你老兄欢迎你。
<强>实施强>
Public Overrides Sub OnMouseDown(ByVal Button As Integer, ByVal Shift As Integer, ByVal X As Integer, ByVal Y As Integer)
Dim getMethod As New DecimalDegreesToDegreesMinutesSeconds
getMethod.PointFromScreenPoint(X, Y)
End Sub
Public Class DecimalDegreesToDegreesMinutesSeconds
' Used by both
Private pSpRFc As ESRI.ArcGIS.Geometry.SpatialReferenceEnvironment
' WGS1984
Private pSpRef1 As ESRI.ArcGIS.Geometry.ISpatialReference
Private pGCS As ESRI.ArcGIS.Geometry.IGeographicCoordinateSystem
'' NAD83 FEET STATEPLANES NC
'Private pSpRef2 As ESRI.ArcGIS.Geometry.ISpatialReference
'Private pPCS As ESRI.ArcGIS.Geometry.IProjectedCoordinateSystem
Private ReadOnly Property WGS84() As ESRI.ArcGIS.Geometry.ISpatialReference
Get
' WGS1984
pSpRFc = New ESRI.ArcGIS.Geometry.SpatialReferenceEnvironment
pGCS = pSpRFc.CreateGeographicCoordinateSystem(4326)
pSpRef1 = pGCS
pSpRef1.SetFalseOriginAndUnits(-180, -90, 1000000)
Return pSpRef1
End Get
End Property
' pass the original screen point into this function
Public Sub PointFromScreenPoint(pX As Double, pY As Double)
Dim scrDisp As ESRI.ArcGIS.Display.IScreenDisplay = Nothing
Dim pnt As ESRI.ArcGIS.Geometry.IPoint = Nothing
Dim pGeoSpRef As ESRI.ArcGIS.Geometry.IGeometry = Nothing
Try
'
scrDisp = New ESRI.ArcGIS.Display.ScreenDisplay
scrDisp = SGProperties.pActiveView.ScreenDisplay ' the activeview
scrDisp.StartDrawing(scrDisp.hDC, CShort(ESRI.ArcGIS.Display.esriScreenCache.esriNoScreenCache))
'
pnt = scrDisp.DisplayTransformation.ToMapPoint(pX, pY)
'
pGeoSpRef = pnt
pGeoSpRef.SpatialReference = SGProperties.pMap.SpatialReference ' the current maps
pGeoSpRef.Project(WGS84())
Windows.Forms.MessageBox.Show("X position is " + ConvertDegrees(pnt.X, DegreesType.Longitude).ToString() + " Y position is " + ConvertDegrees(pnt.Y, DegreesType.Latitude).ToString())
Catch ex As Exception
Finally
If scrDisp IsNot Nothing Then System.Runtime.InteropServices.Marshal.ReleaseComObject(scrDisp)
scrDisp = Nothing
If pnt IsNot Nothing Then System.Runtime.InteropServices.Marshal.ReleaseComObject(pnt)
pnt = Nothing
If pGeoSpRef IsNot Nothing Then System.Runtime.InteropServices.Marshal.ReleaseComObject(pGeoSpRef)
pGeoSpRef = Nothing
End Try
End Sub
Enum DegreesType
Latitude
Longitude
End Enum
Private Function ConvertDegrees(pInDegrees As Double, pInType As DegreesType)
Dim degrees As Integer
Dim submin As Double
Dim minutes As Double
Dim subsecsonds As Double
Dim direction As String
Dim output As String
Try
degrees = Math.Truncate(pInDegrees)
submin = Math.Abs((pInDegrees - Math.Truncate(pInDegrees)) * 60)
minutes = Math.Truncate(submin)
subsecsonds = Math.Abs((submin - Math.Truncate(submin)) * 60)
direction = ""
If pInType.ToString().Trim().ToUpper() = "Latitude".ToUpper() Then
If degrees < 0 Then
direction = "S"
ElseIf (degrees > 0) Then
direction = "N"
Else
direction = ""
End If
ElseIf pInType.ToString().Trim().ToUpper() = "Longitude".ToUpper() Then
If degrees < 0 Then
direction = "W"
ElseIf (degrees > 0) Then
direction = "E"
Else
direction = ""
End If
End If
output = degrees.ToString() + ":" + minutes.ToString() + ":" + subsecsonds.ToString().Substring(0, 5) + direction
Return output
Catch ex As Exception
Return Nothing
End Try
End Function
结束班