ArcEngine 创建要素，删除要素，生成网格（VB）

 Public Function CreateFeatureClass() As IFeatureClass
        Dim pWorkspaceFactory As IWorkspaceFactory = New ESRI.ArcGIS.DataSourcesGDB.AccessWorkspaceFactory
        Dim dataset As IDataset = pPointFeatureLayer.FeatureClass
        Dim featureWorkspace As IFeatureWorkspace = pWorkspaceFactory.OpenFromFile(dataset.Workspace.PathName, 0) ‘dataset.Workspace.PathName="C:\\aa.mdb"
        Dim workspace As IWorkspace2 = featureWorkspace
        Dim featureClassName As String = "New"
        Dim fields As IFields = Nothing
        Dim CLSID As ESRI.ArcGIS.esriSystem.UID = Nothing
        Dim CLSEXT As ESRI.ArcGIS.esriSystem.UID = Nothing
        Dim strConfigKeyword As String = ""
        Dim featureClass As IFeatureClass
        If workspace.NameExists(esriDatasetType.esriDTFeatureClass, featureClassName) Then ‘如果存在删除改要素
            featureClass = featureWorkspace.OpenFeatureClass(featureClassName)
            Dim pDataset As IDataset = featureClass
            pDataset.Delete() ‘删除该要素
        End If
        ‘ 赋值类ID如果未分配
        If CLSID Is Nothing Then
            CLSID = New ESRI.ArcGIS.esriSystem.UID
            CLSID.Value = "esriGeoDatabase.Feature"
        End If
        Dim objectClassDescription As IObjectClassDescription = New FeatureClassDescription
        If fields Is Nothing Then
            ‘ 创建字段
            fields = objectClassDescription.RequiredFields
            Dim fieldsEdit As IFieldsEdit = CType(fields, IFieldsEdit)
            Dim field As IField = New Field
            Dim fieldEdit As IFieldEdit = CType(field, IFieldEdit) ‘ 显示转换
            ‘ 设置字段属性
            fieldEdit.Name_2 = "SampleField"
            fieldEdit.Type_2 = esriFieldType.esriFieldTypeString
            fieldEdit.IsNullable_2 = True
            fieldEdit.AliasName_2 = "Sample Field Column"
            fieldEdit.DefaultValue_2 = "test"
            fieldEdit.Editable_2 = True
            fieldEdit.Length_2 = 100
            ‘添加到字段集中
            fieldsEdit.AddField(field)
            fields = CType(fieldsEdit, IFields)
        End If
        Dim strShapeField As String = ""
        Dim j As Int32
        For j = 0 To fields.FieldCount
            If fields.Field(j).Type = esriFieldType.esriFieldTypeGeometry Then
                strShapeField = fields.Field(j).Name
                Exit For
            End If
        Next j
        Dim fieldChecker As IFieldChecker = New FieldChecker
        Dim enumFieldError As IEnumFieldError = Nothing
        Dim validatedFields As IFields = Nothing
        fieldChecker.ValidateWorkspace = CType(workspace, IWorkspace)
        fieldChecker.Validate(fields, enumFieldError, validatedFields)
        featureClass = featureWorkspace.CreateFeatureClass(featureClassName, validatedFields, CLSID, CLSEXT, esriFeatureType.esriFTSimple, strShapeField, strConfigKeyword)



        ‘添加要素，跟据其他要素的范围，生成一个边长为length的矩形网格用于渲染
        Dim length As Integer = 1000 ‘方块长度
        Dim pLineLayer As ILayer = pLineFeatureLayer
        Dim pEnvelope As IEnvelope = pLineLayer.AreaOfInterest
        Dim XMin As Double = pEnvelope.XMin
        Dim XMax As Double = pEnvelope.XMax

        Dim YMax As Double = pEnvelope.YMax
        Dim newXMin As Double = XMin + length

        Do While newXMin < XMax
            Dim YMin As Double = pEnvelope.YMin
            Dim newYMin As Double = YMin + length
            Do While newYMin < YMax
                AddFeature(XMin, newXMin, YMin, newYMin, featureClass.CreateFeature())
                YMin = newYMin
                newYMin = YMin + length
            Loop
            AddFeature(XMin, newXMin, YMin, newYMin, featureClass.CreateFeature())
            XMin = newXMin
            newXMin = XMin + length
        Loop
        Dim pNewFeatureLayer As IFeatureLayer = New FeatureLayer
        pNewFeatureLayer.FeatureClass = featureClass
        m_MapControl.AddLayer(pNewFeatureLayer, 3)
        m_MapControl.Refresh()
        MessageBox.Show("生成完毕")
    End Function

    Private Function AddFeature(ByVal XMin As Double, ByVal newXMin As Double, ByVal YMin As Double, ByVal newYMin As Double, ByVal pFeature As IFeature)
        Dim pPoint1 As IPoint = New Point()
        pPoint1.X = XMin
        pPoint1.Y = YMin
        Dim pPoint2 As IPoint = New Point()
        pPoint2.X = newXMin
        pPoint2.Y = YMin
        Dim pPoint3 As IPoint = New Point()
        pPoint3.X = newXMin
        pPoint3.Y = newYMin
        Dim pPoint4 As IPoint = New Point()
        pPoint4.X = XMin
        pPoint4.Y = newYMin
        Dim pPOlygon As IPolygon
        Dim pPointColec As IPointCollection = New Polygon
        pPointColec.AddPoint(pPoint1)
        pPointColec.AddPoint(pPoint2)
        pPointColec.AddPoint(pPoint3)
        pPointColec.AddPoint(pPoint4)
        pPOlygon = CType(pPointColec, IPolygon)
        pFeature.Shape = pPOlygon
        pFeature.Store()
    End Function