Private Sub frmAssemble_Load(sender As Object, e As EventArgs) Handles MyBase.Load rwc = New RenderWindowControl PanelRWC.Controls.Add(rwc) rwc.Dock = DockStyle.Fill render = rwc.RenderWindow.GetRenderers().GetFirstRenderer() Interactor = rwc.RenderWindow.GetInteractor() Dim interactorStyle As vtkInteractorStyle = vtkInteractorStyleTrackballCamera.[New] Interactor.SetInteractorStyle(interactorStyle) AddAxesOrientationWidget() End Sub

这是一个VB.NET程序中的一个子程序，它在窗体加载时初始化了一个vtkRenderWindowControl控件，并将其添加到PanelRWC控件中，并将其Dock属性设置为Fill以使其填充整个PanelRWC控件。然后，它获取vtkRenderWindowControl的Renderers集合中的第一个Renderer对象，并将其赋值给变量render。接着，它获取vtkRenderWindowControl的Interactor对象，并创建一个vtkInteractorStyleTrackballCamera对象作为交互器的样式，并将其设置为vtkRenderWindowControl的InteractorStyle。最后，它调用AddAxesOrientationWidget()方法来添加一个坐标轴方向小部件。该程序使用VTK（Visualization Toolkit）来创建可视化对象，并将其显示在窗体上。

相关问题

Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click If Button2.Text = "保存" Then Button2.Text = "修改" End If End Sub Private Sub Button添加_Click(sender As Object, e As EventArgs) Handles Button添加.Click Button2.PerformClick() End Sub并不能成功修改button.text

这段代码存在一个问题，在`Button2_Click`事件中，当按钮文本为“保存”时，它会将按钮文本更改为“修改”，但没有实际修改任何内容。在`Button添加_Click`事件中，它调用了`Button2.PerformClick()`，但这并不会触发`Button2_Click`事件中的代码，因为按钮文本不是“保存”。

要解决这个问题，你需要在`Button2_Click`事件中添加实际的修改代码，例如：

Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
    If Button2.Text = "保存" Then
        Button2.Text = "修改"
        '执行保存操作
    End If
End Sub

然后，在`Button添加_Click`事件中，你可以添加代码来将按钮文本更改为“保存”并触发`Button2_Click`事件：

Private Sub Button添加_Click(sender As Object, e As EventArgs) Handles Button添加.Click
    Button2.Text = "保存"
    Button2.PerformClick()
End Sub

这样，当你单击“添加”按钮时，它将会执行保存操作并将按钮文本更改为“修改”。

Imports System.Data.OleDb Public Class Form3 Dim con As New OleDbConnection Dim adp As New OleDbDataAdapter Dim ds As New DataSet Private Sub Form3_Load(sender As Object, e As EventArgs) Handles MyBase.Load con.ConnectionString = "Provider=SQLOLEDB;Data Source=.;Integrated Security=SSPI;Initial Catalog=students" Dim selectcmd As New OleDbCommand selectcmd.CommandText = "select * from student" selectcmd.Connection = con adp.SelectCommand = selectcmd adp.Fill(ds, "Table") End Sub Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click For Each txt As TextBox In Me.Controls.OfType(Of TextBox)() txt.Text = "" Next For Each combo As ComboBox In Me.Controls.OfType(Of ComboBox)() combo.Text = "" Next End Sub Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click Dim insecmd As New OleDbCommand Dim Vs As String = TextBox1.Text & "','" & TextBox2.Text & "','" & ComboBox1.Text & "','" & ComboBox2.Text & "'," & TextBox3.Text & ",'" & ComboBox3.Text & ComboBox4.Text & ComboBox5.Text & "','" & TextBox4.Text & "','" & ComboBox6.Text & "','" & TextBox5.Text & "')" insecmd.CommandText = "insert into student values('" & Vs insecmd.Connection = con adp.InsertCommand = insecmd adp.Update(ds) End Sub End Class这段代码有什么问题

这段代码有几个问题：

1. 连接字符串是针对 SQL Server 的，而不是 Access 数据库。应该使用 Access 数据库的连接字符串，例如：

   con.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\MyDatabase.mdb"

2. 在插入数据时，字符串值应该使用参数化查询，而不是将值直接拼接到 SQL 语句中。这样可以避免 SQL 注入攻击，并且可以自动处理特殊字符的转义。应该改为类似下面的语句：

   insecmd.CommandText = "insert into student values(?, ?, ?, ?, ?, ?, ?, ?, ?)"
   insecmd.Parameters.AddWithValue("param1", TextBox1.Text)
   insecmd.Parameters.AddWithValue("param2", TextBox2.Text)
   '...

3. 在清空表单数据时，应该检查控件的类型是否为 TextBox 或 ComboBox，否则可能会出现异常。可以改为类似下面的语句：

   For Each ctrl As Control In Me.Controls
       If TypeOf ctrl Is TextBox Then
           DirectCast(ctrl, TextBox).Text = ""
       ElseIf TypeOf ctrl Is ComboBox Then
           DirectCast(ctrl, ComboBox).Text = ""
       End If
   Next

4. 在插入数据后应该更新 DataSet 中的数据，以便在下一次查询中可以看到新插入的记录。可以改为类似下面的语句：

   adp.Update(ds, "Table")

根据上述建议，可以将代码修改为：

Imports System.Data.OleDb

Public Class Form3
    Dim con As New OleDbConnection
    Dim adp As New OleDbDataAdapter
    Dim ds As New DataSet

    Private Sub Form3_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        con.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\MyDatabase.mdb"
        Dim selectcmd As New OleDbCommand
        selectcmd.CommandText = "select * from student"
        selectcmd.Connection = con
        adp.SelectCommand = selectcmd
        adp.Fill(ds, "Table")
    End Sub

    Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
        For Each ctrl As Control In Me.Controls
            If TypeOf ctrl Is TextBox Then
                DirectCast(ctrl, TextBox).Text = ""
            ElseIf TypeOf ctrl Is ComboBox Then
                DirectCast(ctrl, ComboBox).Text = ""
            End If
        Next
    End Sub

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Dim insecmd As New OleDbCommand
        insecmd.CommandText = "insert into student values(?, ?, ?, ?, ?, ?, ?, ?, ?)"
        insecmd.Parameters.AddWithValue("param1", TextBox1.Text)
        insecmd.Parameters.AddWithValue("param2", TextBox2.Text)
        insecmd.Parameters.AddWithValue("param3", ComboBox1.Text)
        insecmd.Parameters.AddWithValue("param4", ComboBox2.Text)
        insecmd.Parameters.AddWithValue("param5", TextBox3.Text)
        insecmd.Parameters.AddWithValue("param6", ComboBox3.Text & ComboBox4.Text & ComboBox5.Text)
        insecmd.Parameters.AddWithValue("param7", TextBox4.Text)
        insecmd.Parameters.AddWithValue("param8", ComboBox6.Text)
        insecmd.Parameters.AddWithValue("param9", TextBox5.Text)
        insecmd.Connection = con
        adp.InsertCommand = insecmd
        adp.Update(ds, "Table")
    End Sub
End Class