arcengineStatistics 
By  yumao  2007-7-18 0:25:00   

ͳƣBaseStatisticsɺͱͳƽIFrequencyStatisticsӿṩƵͳƵĳԱķʡIGenerateStatisticsӿṩͳƽĳԱķʡIStatisticsResultsṩͳƽĳԱķʡɷʵCount,Sum,Maximum,Minimum,Meanm,StandardDeviation(׼) 
DataStatisticsͳƽֶεΨһֵͨIDataStatistics::CursorԣԹʽĴ롣עICursorĶֻʹһΣҪȡӦٴδꡣ
IDataStatisticsͳΨһĽӿڣӣ
Dim pFeatLyr As IFeatureLayer
        pFeatLyr = New FeatureLayer

        Dim pMap As IMap
        pMap = AxMapControl1.Map
        Dim i As Integer
        For i = 0 To pMap.LayerCount - 1
            If pMap.Layer(i).Name = "STATES" Then
                pFeatLyr = pMap.Layer(i)
                Exit For
            End If
        Next
        Dim pFeatClass As IFeatureClass
        pFeatClass = pFeatLyr.FeatureClass

        Dim pDataStatistics As IDataStatistics
        pDataStatistics = New DataStatistics
        Dim pFeatCursor As IFeatureCursor
        pFeatCursor = pFeatClass.Search(Nothing, False)
        Dim pCursor As ICursor
        pCursor = pFeatCursor

        pDataStatistics.Cursor = pCursor
        pDataStatistics.Field = "AREA_1"

        Dim pStaResult As IStatisticsResults
        pStaResult = pDataStatistics.Statistics
        Dim num As Long
        Dim dMax As Double
        Dim dMin As Double
        Dim dMean As Double
        num = pStaResult.Count
        dMax = pStaResult.Maximum
        dMin = pStaResult.Minimum
        dMean = pStaResult.Mean
        MessageBox.Show("" + num.ToString + "ݣǣ" + dMax.ToString + "Сǣ" + dMin.ToString + "ƽǣ" + dMean.ToString)
 
 
