VB+ArcGis Engine 开发零基础GIS程序框架教程

VB+ArcGis Engine开发零基础GIS程序框架教程第一步配置环境和设计界面环境：ArcGisEngine 9.1 + Microsoft Visual Basic 6.0使用Engine控件：ESRI ToolbarControl, ESRITOCControl 、ESRILicenseControl、ESRIMapControl。

（按Ctrl+T调出部件面板，选中以下控件）再从[工程]-[引用]添加一下引用：界面布局（右侧大的MapcControl命名为MapControl1，为显示地图主界面。

左下角的MapcControl命名为MapControl2，作为地图鹰眼。

在工具栏里添加如图的几个按钮即可。

其它再添加一个CommonDialog1和状态栏）：在ESRI ToccControl和 ESRIToolbarControl属性里绑定控件EsriMapControl （buddy选择MapControl1）。

这样基本界面就布置好了。

第二步加载地图代码为：'打开地图文档On Error Resume NextDim sFileName As StringWith CommonDialog1.DialogTitle = "Open Map Document".Filter = "Map Documents (*.mxd;*.pmf)|*.mxd;*.pmf".ShowOpenIf .FileName = "" Then Exit SubsFileName = .FileNameEnd WithIf MapControl1.CheckMxFile(sFileName) ThenMapControl1.LoadMxFile sFileNameMapControl1.Extent = MapControl1.FullExtentElseMsgBox sFileName & " is not a valid ArcMap document"Exit SubEnd IfStatusBar1.Panels(3).Text = sFileName ‘状态栏显示文件路径第三步让鹰眼地图跟MapControl1的地图互动1.先在声明里定义几个变量：'地图鹰眼Private m_pEnvelope As IEnvelope ' The envelope drawn on the MapControl Private m_pFillSymbol As ISimpleFillSymbol' The symbol used to draw the Private WithEvents m_pTransformEvents AsdisplayTransformation2.定义如下函数：Private Sub CreateOverviewSymbol() '设置鹰眼图中的红线框'Get the IRgbColor interface.DimpColor As IRgbColorSetpColor = New RgbColor'Set the color properties.pColor.RGB = RGB(255, 0, 0)'Get the ILine symbol interface.Dim pOutline As ILineSymbolSetpOutline = New SimpleLineSymbol'Set the line symbol properties.pOutline.Width = 1.5pOutline.Color = pColor'Get the IFillSymbol interface.Setm_pFillSymbol = New SimpleFillSymbol'Set the fill symbol properties.m_pFillSymbol.Outline = pOutlinem_pFillSymbol.Style = esriSFSHollowEnd SubPrivate Sub MapControl2_OnAfterDraw(ByValdisplay As Variant, ByVal viewDrawPhase As Long)Ifm_pEnvelope Is Nothing Then Exit Sub'If the foreground phase has drawnDimpViewDrawPhase As esriViewDrawPhasepViewDrawPhase = viewDrawPhaseIfpViewDrawPhase = esriViewForeground Then'Draw the shape on the MapControl.MapControl2.DrawShape m_pEnvelope, m_pFillSymbolEndIfEnd SubPrivate Sub m_pTransformEvents_VisibleBoundsUpdated(ByValsender As esriDisplay.IDisplayTransformation, ByVal sizeChanged As Boolean)'Set the extent to the new visible extent.Setm_pEnvelope = sender.VisibleBounds'Refresh the MapControl's foreground phase.MapControl2.RefreshesriViewForegroundEnd Sub3.在Form_Load 事件中调用CreateOverviewSymbol：Private Sub Form_Load()Call CreateOverviewSymbolEnd Sub4.在MapControl1的OnMapReplaced中加入以下代码：Private Sub MapControl1_OnMapReplaced(ByValnewMap As Variant)'当主地图显示控件的地图改变时，鹰眼中的地图也跟随改变'Get the IActiveView of the focus map in the PageLayoutControl. DimpActiveView As IActiveViewSetpActiveView = MapControl1.ActiveView.FocusMap'Trap the ITransformEvents of the PageLayoutControl's focus map. Setm_pTransformEvents =pActiveView.ScreenDisplay.displayTransformation'Get the extent of the focus map.Setm_pEnvelope = pActiveView.Extent'Load the same preauthored map document into the MapControl. MapControl2.LoadMxFile MapControl1.DocumentFilename'Set the extent of the MapControl to the full extent of the data. MapControl2.Extent = MapControl2.FullExtentEnd Sub5.当点击鹰眼中的某个地方时，主窗口的地图跟随着改变：Private Sub MapControl2_OnMouseDown(ByValbutton As Long, ByVal shift As Long, ByVal x As Long, ByVal y As Long, ByValmapX As Double, ByVal mapY As Double)Dim pPt As IPointSet pPt = New PointpPt.PutCoords mapX, mapY'改变主控件的视图范围MapControl1.CenterAt pPtEnd Sub这样地图鹰眼就做好了。

第四步显示当前地图比例尺及自定义比例尺显示地图Private SubMapControl1_OnExtentUpdated(ByVal displayTransformation As Variant, ByValsizeChanged As Boolean, ByVal newEnvelope As Variant) Label1.Caption = "1:" & MapControl1.MapScale '显示比例尺Text1.Text = MapControl1.MapScaleEnd SubPrivate Sub Command4_Click()'设置地图显示比例尺MapControl1.MapScale = Val(Text1.Text)MapControl1.RefreshEnd Sub第五步在状态栏上显示当前鼠标位置坐标：首先需要当前地图所采用的坐标单位，需要在声明里定义变量sMapUnits：Private sMapUnits As String '显示坐标用然后在MapControl1_OnMapReplaced里增加代码：Dim pMapUnits As esriUnitspMapUnits = MapControl1.MapUnitsIfpMapUnits = esriCentimeters ThensMapUnits = "Centimeters"ElseIf pMapUnits = esriDecimalDegrees ThensMapUnits = "Decimal Degrees"ElseIf pMapUnits = esriDecimeters ThensMapUnits = "Decimeters"ElseIf pMapUnits = esriFeet ThensMapUnits = "Feet"ElseIf pMapUnits = esriInches ThensMapUnits = "Inches"ElseIf pMapUnits = esriKilometers ThensMapUnits = "Kilometers"ElseIf pMapUnits = esriMeters ThensMapUnits = "Meters"ElseIf pMapUnits = esriMiles ThensMapUnits = "Miles"ElseIf pMapUnits = esriMillimeters ThensMapUnits = "Millimeters"ElseIf pMapUnits = esriNauticalMiles ThensMapUnits = "NauticalMiles"ElseIf pMapUnits = esriPoints ThensMapUnits = "Points"ElseIf pMapUnits = esriUnknownUnits ThensMapUnits = "Unknown"ElseIf pMapUnits = esriYards ThensMapUnits = "Yards"EndIf接下来只要在MapControl1_OnMouseMove里添加代码：Private Sub MapControl1_OnMouseMove(ByValbutton As Long, ByVal shift As Long, ByVal x As Long, ByVal y As Long, ByValmapX As Double, ByVal mapY As Double)'状态栏上显示坐标StatusBar1.Panels(2).Text =Format(mapX, ".00") & " , " & Format(mapY, ".00") & " " &sMapUnitsEnd Sub第六步将当前视图范围内的地图导出Jpg格式的图片'把地图保存为图片CommonDialog1.FileName = ""CommonDialog1.Filter = "JPG图片(*.JPG)|*.jpg"CommonDialog1.ShowSaveIf CommonDialog1.FileName <> "" ThenDim lScrRes As LonglScrRes=Me.MapControl1.ActiveView.ScreenDisplay.displayTransformation.Resolu tionDim pExporter As IExporterSet pExporter = New JpegExporterpExporter.ExportFileName = CommonDialog1.FileNamepExporter.Resolution = lScrResDim deviceRECT As tagRECTdeviceRECT=Me.MapControl1.ActiveView.ScreenDisplay.displayTransformation.Device FrameDim pDriverBounds As IEnvelopeSet pDriverBounds = New EnvelopepDriverBounds.PutCoords deviceRECT.Left,deviceRECT.bottom,deviceRECT.Right, deviceRECT.ToppExporter.PixelBounds = pDriverBoundsDim pCancel As ITrackCancelSet pCancel = New CancelTrackerMe.MapControl1.ActiveView.Output pExporter.StartExporting,lScrRes,deviceRECT, Me.MapControl1.ActiveView.Extent, pCancel pExporter.FinishExportingEnd If当时做这一步的时候出了点小问题，Set pDriverBounds = New Envelope 这句老是编译出错，提示“无效使用New关键字”。