一次性将数据填充到多个文本框

Question

我有一个包含6个组框的表单，每个组框包含180个文本框以及两个组合框。在从第一个组合框中选择一个值时，第二个组合框将从表中填充所需的数据。我的要求是，从第二个组合框中选择一个值时，来自同一个表的过滤数据应该填充剩余的文本框。我使用的代码如下：

Private Sub ComboBox2_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ComboBox2.SelectedIndexChanged 
    Dim strConnection As String = "Provider=Microsoft.Jet.OleDb.4.0; Data Source=c:\\users\\brisingr\\documents\\123\database.mdb" 
    Dim objConnection As New OleDbConnection(strConnection) 

    Dim strsql As String 
    'strsql = "Select * from '" & ComboBox1.Text & "' where Style = '" & ComboBox2.Text & " '" 
    Dim a As String 
    Dim b As String 
    Dim c As String 
    Dim d As String 
    a = "Select * from [" 
    b = ComboBox1.Text 
    c = "] where Style = [" 
    d = ComboBox2.Text 
    strsql = a & b & c & d & "]" 
    Dim objCommand As New OleDbCommand(strsql, objConnection) 

    Dim objDataAdapter As New OleDbDataAdapter(objCommand) 
    Dim objDataTable As New DataTable("Buyers") 
    objDataAdapter.Fill(objDataTable) 

    objConnection.Close() 
    objConnection.Dispose() 
    objConnection = Nothing 
    objCommand.Dispose() 
    objCommand = Nothing 
    objDataAdapter.Dispose() 
    objDataAdapter = Nothing 

    For i As Integer = 1 To 60 
     Me.Controls("L1Ob" & i).Text = objDataTable.Rows(0)("Operation" & i) 
    Next 

End Sub 

这里的“操作” &（我）是指数据库，已命名为喜欢的operation1，操作2等的字段名...

这段代码似乎不适合我。请帮助..

Answer 1

在这里，我们有很多问题

Dim a As String 
Dim b As String 
Dim c As String 
Dim d As String 
a = "Select * from [" 
b = ComboBox1.Text 
c = "] where Style = [" 
d = ComboBox2.Text 
strsql = a & b & c & d & "]" 
Dim objCommand As New OleDbCommand(strsql, objConnection) 

首先，你必须通过周围的场Style值方括号。
而这不是一个有效的语法。 Jet引擎假定这是一个参数。其实，传递一个参数是正确的选择。

a = "Select * from [" 
b = ComboBox1.Text 
c = "] where Style = ?" 
strsql = a & b & c 
Dim objCommand As New OleDbCommand(strsql, objConnection) 
objCommand.Parameters.AddWithValue("@p1", ComboBox2.Text) 
Dim objDataAdapter As New OleDbDataAdapter(objCommand) 
Dim objDataTable As New DataTable("Buyers") 
objDataAdapter.Fill(objDataTable) 

该字段Style的值通过参数传递。这留下了将组合框的值替换为占位符（？）的工作。
你可以肯定，它知道更好的做，避免错误和sql注入。

此代码仍然很弱。您应该确保第一个组合框1的内容不能被修改为包含恶意文本而不是表名称