[求助]ArcGIS里怎样求圆心的坐标？

<P>ArcGIS里怎样求圆心的坐标？</P>
<P>就是知道一个圆。代码应该怎么写啊？谢谢大家了</P>

怎么没有人回复啊？

听别人说有个centerid属性,改怎么用啊?

<P>C#中:</P>
<P>IArea area = obj as IArea</P>
<P>然后调用area.Centroid</P>
<P>obj为圆对象 </P>
<P>同样方法可以求出其他图形的中心（质心），详见AO</P>

<H1>Area Example</H1><PRE><PRE><CODE><PRE>' The example shows how to get the properties for a selected polygon in
' an ArcMap edit session.

Public Sub t_IArea_polygon()
   Dim pID As New UID
   pID = "esriEditor.editor"
   Dim pEditor As IEditor
   Dim pApp As IApplication
   Set pApp = Application
   Set pEditor = pApp.FindExtensionByCLSID(pID)
  
   If pEditor.SelectionCount <>  1 Then
     MsgBox "select one polygon"
     Exit Sub
   End If
  
   Dim pEnumFeat As IEnumFeature
   Dim pFeature As IFeature
   Dim i As Long

   Set pEnumFeat = pEditor.EditSelection

   Dim pArea As IArea
   Dim pCenter As IPoint
   Dim pLabel As IPoint
   Set pCenter = New Point
   Set pLabel = New Point

   Set pFeature = pEnumFeat.Next

   While Not pFeature Is Nothing
     If pFeature.Shape.GeometryType = esriGeometryPolygon Then
       Set pArea = pFeature.Shape
       MsgBox "+++Polygon::IArea properties..." ; vbCrLf _
       ; "Area = " ; pArea.Area ; vbCrLf _
       ; "Center.X = " ; pArea.Centroid.X ; vbCrLf _
       ; "Center.Y = " ; pArea.Centroid.Y ; vbCrLf _
       ; pArea.LabelPoint.X ; vbCrLf _
       ; "LabelPoint.Y = " ; pArea.LabelPoint.Y

       pArea.QueryCentroid pCenter
       pArea.QueryLabelPoint pLabel
       MsgBox "+++Polygon::IArea Queries..." ; vbCrLf _
       ; "Center = " ; pCenter.X ; "," ; pCenter.Y ; vbCrLf _
       ; "Label = " ; pLabel.X ; "," ; pLabel.Y ; vbCrLf

     End If
     Set pFeature = pEnumFeat.Next
   Wend

End Sub</PRE></CODE></PRE></PRE>

<P>呵呵,非常感谢<a href="http://www.gisempire.com/bbs/dispuser.asp?name=xxhhoddity" target="_blank" ><FONT color=#000000>xxhhoddity</FONT></A></P>
<P>那圆要是线状的呢?我是从CAD图里倒过来的,本来是点,却变成了一个小圈,我想再把点还原回去,只能是找圆心坐标了!谢谢啊!</P>

线状的，你去获得IEnvelop接口（包络矩形）