form05.frm

给出了详细的vb环境下mo基本功能的代码 如图层的加载

VERSION 5.00
Object = "{9BD6A640-CE75-11D1-AF04-204C4F4F5020}#2.0#0"; "mo20.ocx"
Begin VB.Form Form05 
   Caption         =   "墨西哥地图"
   ClientHeight    =   6510
   ClientLeft      =   60
   ClientTop       =   345
   ClientWidth     =   9825
   LinkTopic       =   "Form1"
   ScaleHeight     =   6510
   ScaleWidth      =   9825
   StartUpPosition =   2  '屏幕中心
   Begin VB.CheckBox Check4 
      Caption         =   "城市名称"
      Height          =   375
      Left            =   120
      TabIndex        =   4
      Top             =   2760
      Value           =   1  'Checked
      Width           =   1095
   End
   Begin VB.CheckBox Check3 
      Caption         =   "州界"
      Height          =   495
      Left            =   120
      TabIndex        =   3
      Top             =   2280
      Value           =   1  'Checked
      Width           =   855
   End
   Begin VB.CheckBox Check2 
      Caption         =   "河流"
      Height          =   495
      Left            =   120
      TabIndex        =   2
      Top             =   1800
      Value           =   1  'Checked
      Width           =   855
   End
   Begin VB.CheckBox Check1 
      Caption         =   "城市"
      Height          =   495
      Left            =   120
      TabIndex        =   1
      Top             =   1320
      Value           =   1  'Checked
      Width           =   855
   End
   Begin MapObjects2.Map Map1 
      Height          =   6495
      Left            =   1320
      TabIndex        =   0
      Top             =   0
      Width           =   8460
      _Version        =   131072
      _ExtentX        =   14922
      _ExtentY        =   11456
      _StockProps     =   225
      BackColor       =   16777215
      BorderStyle     =   1
      Contents        =   "Form05.frx":0000
   End
End
Attribute VB_Name = "Form05"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
'Xue Wei,2003/5/2
'用Check控件控制图层的显示。

Option Explicit
Dim dc As New DataConnection
Dim layer As MapLayer

Private Sub Check3_Click()
  Set layer = Map1.Layers(2)
  If Check3.Value = 0 Then
    layer.Visible = False
  Else
    layer.Visible = True
  End If
  Map1.Refresh
End Sub

Private Sub Check2_Click()
  Set layer = Map1.Layers(1)
  If Check2.Value = 0 Then
    layer.Visible = False
  Else
    layer.Visible = True
  End If
  Map1.Refresh
End Sub

Private Sub Check1_Click()
  Set layer = Map1.Layers(0)
  If Check1.Value = 0 Then
    layer.Visible = False
  Else
    layer.Visible = True
  End If
  Map1.Refresh
End Sub

Private Sub Check4_Click()
  Set layer = Map1.Layers(0)
  Set layer.Renderer = New LabelRenderer
  If Check4.Value = 0 Then
    layer.Renderer.AllowDuplicates = False
  Else
    Call Layer0Render(layer)
  End If
  Map1.Refresh
End Sub

Private Sub Layer0Render(layer1 As MapLayer)
  Set layer1.Renderer = New LabelRenderer
  layer1.Renderer.Field = "NAME"      '指定要显示的字段
  'layer1.Renderer.Symbol(0).Font.Name = "Times New Roman"
  layer1.Renderer.Symbol(0).Font.Bold = False     '缺省为True
  layer1.Renderer.Symbol(0).Color = moBlack
  layer1.Renderer.Symbol(0).Font.Size = 8
  layer1.Renderer.AllowDuplicates = True
End Sub

Private Sub LayerSet()
  Set layer = New MapLayer
  Set layer.GeoDataset = dc.FindGeoDataset("States")
  layer.Symbol.Color = moYellow
  layer.Symbol.Size = 1
  'layer.Symbol.Style = 2
  layer.Symbol.OutlineColor = moBrown
  Map1.Layers.Add layer
  
  Set layer = New MapLayer
  Set layer.GeoDataset = dc.FindGeoDataset("Rivers")
  layer.Symbol.Color = moDarkGreen
  layer.Symbol.Size = 2
  Map1.Layers.Add layer
  
  Set layer = New MapLayer
  Set layer.GeoDataset = dc.FindGeoDataset("Cities")
  layer.Symbol.Color = moRed
  layer.Symbol.Size = 4
  layer.Symbol.Style = 0
  Call Layer0Render(layer)
  Map1.Layers.Add layer
End Sub

Private Sub Form_Load()
  dc.Database = App.Path + "\..\" + "Mexico"
  If Not dc.Connect Then
    MsgBox "在指定的文件夹下没找到图层数据文件！"
    End
  End If
  LayerSet
  Map1.Refresh
End Sub