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  • 对featureclass中插入和删除feature的几种方法进行了比较

    本文对featureclass中插入和删除feature的几种方法进行了比较。

    一、插入单个feature,方法1和方法2差别不大

    方法1:

     ''' <summary>
      ''' 向featureclass中插入feature
      ''' </summary>
      ''' <param name="pFeatureClass">要插入的featureclass</param>
      ''' <remarks></remarks>
      Private Sub InsertFeature(ByVal pFeatureClass As IFeatureClass, ByVal pGeo As IGeometry)
        If pFeatureClass Is Nothing Then Exit Sub
        Dim pFeatBuf As IFeatureBuffer = pFeatureClass.CreateFeatureBuffer()
        Dim pFeat As IFeature = pFeatBuf
        Dim pFeatCur As IFeatureCursor = pFeatureClass.Insert(True)
        pFeat.Shape = pGeo
        pFeatCur.InsertFeature(pFeatBuf)
        pFeatCur.Flush()
      End Sub

     方法2:
      ''' <summary>
      ''' 向featureclass中插入feature
      ''' </summary>
      ''' <param name="pFeatureClass">要插入的featureclass</param>
      ''' <remarks></remarks>
      Private Sub InsertFeature1(ByVal pFeatureClass As IFeatureClass, ByVal pGeo As IGeometry)
        If pFeatureClass Is Nothing Then Exit Sub
        Dim pFeature As IFeature = pFeatureClass.CreateFeature()
        pFeature.Shape = pGeo
        pFeature.Store()
      End Sub

    二、批量插入feature,如果用feature.store,一个个插入,较之buffer方法,会慢很多

    方法1:

      ''' <summary>
      ''' 向featureclass中批量插入features
      ''' </summary>
      ''' <param name="pFeatureClass">要插入的featureclass</param>
      ''' <remarks>批量插入features,用buffer的方法,要比循环一个个Store的方法快</remarks>
      Public Sub InsertFeatures(ByVal pFeatureClass As IFeatureClass, ByVal pGeos As List(Of IGeometry))
        If pFeatureClass Is Nothing Then Exit Sub
        Dim pFeatBuf As IFeatureBuffer = pFeatureClass.CreateFeatureBuffer()
        Dim pFeat As IFeature = pFeatBuf
        Dim pFeatCur As IFeatureCursor = pFeatureClass.Insert(True)
        For i As Integer = 0 To pGeos.Count - 1
          pFeat.Shape = pGeos(i)
          pFeatCur.InsertFeature(pFeatBuf)
          ''避免一次flush,导致速度过慢
          If i Mod 100 = 0 Then
            pFeatCur.Flush()
          End If
        Next
        pFeatCur.Flush()
      End Sub

    三、删除feature,一个个删除就用IFeature.Delete方法即可,此处不再赘述,只写一种批量删除的方法,用于ITable是真对数据库进行操作的,所以速度很快

    其中方法2是行不通的,会弹出“集合中找不到此项目”的错误。

    方法1:

      ''' <summary>
      ''' 删除某featurelayer中所有feature
      ''' </summary>
      ''' <param name="pLayer">操作的涂层</param>
      ''' <remarks>该方法可以给一个queryfilter,进行删除符合条件的features</remarks>
      Private Sub DeleteAllFeatures(ByVal pLayer As IFeatureLayer)
        Dim pTable As ITable = pLayer.FeatureClass
        pTable.DeleteSearchedRows(Nothing)
      End Sub

    方法2:
      ''' <summary>
      ''' 删除featurecursor中的features
      ''' </summary>
      ''' <param name="pFeatureCursor"></param>
      ''' <remarks>这种方法是行不通的,至少92是这样的,没有实现该方法</remarks>
      Private Sub DeleteFeatures(ByVal pFeatureCursor As IFeatureCursor)
        pFeatureCursor.DeleteFeature()
      End Sub

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  • 原文地址:https://www.cnblogs.com/xianyin05/p/3022088.html
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