frmbus.vb

继续上传经典GIS二次开发书籍系列

Public Class frmBus
    Inherits System.Windows.Forms.Form

    Private _frmMain As MainForm
    Private _bTextBox1 As Boolean = True
    Private _bTextBox2 As Boolean = True

#Region " Windows 窗体设计器生成的代码 "

    Public Sub New(ByVal frmMain As MainForm)
        MyBase.New()

        '该调用是 Windows 窗体设计器所必需的。
        InitializeComponent()

        '在 InitializeComponent() 调用之后添加任何初始化
        _frmMain = frmMain
    End Sub

    '窗体重写处置以清理组件列表。
    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        If disposing Then
            If Not (components Is Nothing) Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub

    'Windows 窗体设计器所必需的
    Private components As System.ComponentModel.IContainer

    '注意：以下过程是 Windows 窗体设计器所必需的
    '可以使用 Windows 窗体设计器修改此过程。
    '不要使用代码编辑器修改它。
    Friend WithEvents _label_end As System.Windows.Forms.Label
    Friend WithEvents _label_start As System.Windows.Forms.Label
    Friend WithEvents _listBox_end As System.Windows.Forms.ListBox
    Friend WithEvents _listBox_start As System.Windows.Forms.ListBox
    Friend WithEvents _button_search As System.Windows.Forms.Button
    Friend WithEvents _textBox_end As System.Windows.Forms.TextBox
    Friend WithEvents _textBox_start As System.Windows.Forms.TextBox
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me._label_end = New System.Windows.Forms.Label()
        Me._label_start = New System.Windows.Forms.Label()
        Me._listBox_end = New System.Windows.Forms.ListBox()
        Me._listBox_start = New System.Windows.Forms.ListBox()
        Me._button_search = New System.Windows.Forms.Button()
        Me._textBox_end = New System.Windows.Forms.TextBox()
        Me._textBox_start = New System.Windows.Forms.TextBox()
        Me.SuspendLayout()
        '
        '_label_end
        '
        Me._label_end.Font = New System.Drawing.Font("宋体", 10.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(134, Byte))
        Me._label_end.Location = New System.Drawing.Point(152, 8)
        Me._label_end.Name = "_label_end"
        Me._label_end.Size = New System.Drawing.Size(80, 16)
        Me._label_end.TabIndex = 21
        Me._label_end.Text = "终点站:"
        '
        '_label_start
        '
        Me._label_start.Font = New System.Drawing.Font("宋体", 10.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(134, Byte))
        Me._label_start.Location = New System.Drawing.Point(8, 8)
        Me._label_start.Name = "_label_start"
        Me._label_start.Size = New System.Drawing.Size(80, 16)
        Me._label_start.TabIndex = 20
        Me._label_start.Text = "起点站:"
        '
        '_listBox_end
        '
        Me._listBox_end.ItemHeight = 12
        Me._listBox_end.Location = New System.Drawing.Point(152, 56)
        Me._listBox_end.Name = "_listBox_end"
        Me._listBox_end.Size = New System.Drawing.Size(128, 208)
        Me._listBox_end.TabIndex = 19
        '
        '_listBox_start
        '
        Me._listBox_start.ItemHeight = 12
        Me._listBox_start.Location = New System.Drawing.Point(8, 56)
        Me._listBox_start.Name = "_listBox_start"
        Me._listBox_start.Size = New System.Drawing.Size(128, 208)
        Me._listBox_start.TabIndex = 18
        '
        '_button_search
        '
        Me._button_search.Location = New System.Drawing.Point(296, 24)
        Me._button_search.Name = "_button_search"
        Me._button_search.Size = New System.Drawing.Size(72, 24)
        Me._button_search.TabIndex = 17
        Me._button_search.Text = "查询"
        '
        '_textBox_end
        '
        Me._textBox_end.Location = New System.Drawing.Point(152, 24)
        Me._textBox_end.Name = "_textBox_end"
        Me._textBox_end.Size = New System.Drawing.Size(128, 21)
        Me._textBox_end.TabIndex = 16
        Me._textBox_end.Text = ""
        '
        '_textBox_start
        '
        Me._textBox_start.Location = New System.Drawing.Point(8, 24)
        Me._textBox_start.Name = "_textBox_start"
        Me._textBox_start.Size = New System.Drawing.Size(128, 21)
        Me._textBox_start.TabIndex = 15
        Me._textBox_start.Text = ""
        '
        'frmBus
        '
        Me.AutoScaleBaseSize = New System.Drawing.Size(6, 14)
        Me.ClientSize = New System.Drawing.Size(376, 273)
        Me.Controls.AddRange(New System.Windows.Forms.Control() {Me._label_end, Me._label_start, Me._listBox_end, Me._listBox_start, Me._button_search, Me._textBox_end, Me._textBox_start})
        Me.FormBorderStyle = System.Windows.Forms.FormBorderStyle.SizableToolWindow
        Me.Name = "frmBus"
        Me.StartPosition = System.Windows.Forms.FormStartPosition.CenterParent
        Me.Text = "选择乘车路线"
        Me.ResumeLayout(False)

    End Sub

#End Region
    '---------------------------------------------------------------------
    Private Sub frmBus_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Load
        LoadListBox()
    End Sub
    '---------------------------------------------------------------------
    Private Sub LoadListBox()
        _listBox_start.DataSource = _frmMain._environment.m_dataSet.Tables("公交车站")
        _listBox_start.DisplayMember = "站名"
        _listBox_end.DataSource = _frmMain._environment.m_dataSet.Tables("公交车站2")
        _listBox_end.DisplayMember = "站名"
    End Sub
    '---------------------------------------------------------------------
    Private Sub _listBox_start_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles _listBox_start.SelectedIndexChanged
        If Not _bTextBox1 Then
            _textBox_start.Text = _listBox_start.Text
        End If
    End Sub
    '---------------------------------------------------------------------
    Private Sub _listBox_end_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles _listBox_end.SelectedIndexChanged
        If Not _bTextBox2 Then
            _textBox_end.Text = _listBox_end.Text
        End If
    End Sub
    '---------------------------------------------------------------------
    Private Sub _listBox_start_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles _listBox_start.MouseDown
        _bTextBox1 = False
    End Sub
    '---------------------------------------------------------------------
    Private Sub _listBox_end_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles _listBox_end.MouseDown
        _bTextBox2 = False
    End Sub
    '---------------------------------------------------------------------
    Private Sub _textBox_start_TextChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles _textBox_start.TextChanged
        Dim nIndex As Integer = _listBox_start.FindString(_textBox_start.Text, -1)
        If nIndex <> ListBox.NoMatches Then
            _listBox_start.SelectedIndex = nIndex
        End If

        If _textBox_end.Text <> "" And _textBox_start.Text <> "" Then
            _button_search.Enabled = True
        Else
            _button_search.Enabled = False
        End If
        _bTextBox1 = True
    End Sub
    '---------------------------------------------------------------------
    Private Sub _textBox_end_TextChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles _textBox_end.TextChanged
        Dim nIndex As Integer = _listBox_end.FindString(_textBox_end.Text, -1)
        If nIndex <> ListBox.NoMatches Then
            _listBox_end.SelectedIndex = nIndex
        End If

        If _textBox_end.Text <> "" And _textBox_start.Text <> "" Then
            _button_search.Enabled = True
        Else
            _button_search.Enabled = False
        End If
        _bTextBox2 = True
    End Sub
    '---------------------------------------------------------------------
    Private Sub _button_search_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles _button_search.Click
        ' 判断站名的正确性
        If Not IsValidStation(_textBox_start.Text) Then
            MessageBox.Show("错误的起始站名。", "北京市地理信息公众查询系统", _
                            MessageBoxButtons.OK, MessageBoxIcon.Information)
            Return
        End If
        If Not IsValidStation(_textBox_end.Text) Then
            MessageBox.Show("错误的终点站名。", "北京市地理信息公众查询系统", _
                            MessageBoxButtons.OK, MessageBoxIcon.Information)
            Return
        End If

        ' 调用CPath类的Search方法公交乘车路线执行查询
        Dim env As CEnvironment = _frmMain._environment
        System.Windows.Forms.Cursor.Current = System.Windows.Forms.Cursors.WaitCursor
        Dim array As New ArrayList()
        env.m_path.Search(_textBox_start.Text, _textBox_end.Text, array)
        System.Windows.Forms.Cursor.Current = System.Windows.Forms.Cursors.Arrow

        If array.Count = 0 Then
            MessageBox.Show("没有合适的乘车路线。", "北京市地理信息公众查询系统", _
                                  MessageBoxButtons.OK, MessageBoxIcon.Information)
            Return
        Else
            ' 如果有匹配的公交换乘方案，则新弹出一窗口，显示查询结果
            Dim frm As New frmBusResult(_frmMain, array)
            Visible = False
            frm.ShowDialog(_frmMain)
            Close()
        End If
    End Sub
    '---------------------------------------------------------------------
    Private Function IsValidStation(ByVal szStation As String) As Boolean
        ' 从“公交车站”表中查询是否有该站点名，如果有则返回true，否则返回false
        Dim indexTbl As System.Data.DataTable
        indexTbl = _frmMain._environment.m_dataSet.Tables("公交车站")
        Dim rowsType As System.Data.DataRow() = indexTbl.Select("站名='" + szStation + "'")
        If rowsType.Length > 0 Then
            Return True
        End If
        Return False
    End Function
    '---------------------------------------------------------------------
End Class