Vb.net 使组合框在禁用时可见

我正在禁用VB.net中的combobox。 但在禁用模式下，它无法正常显示。 我试着改变背景色和前景色，但都不起作用

代码：

cmbbox.BackColor = Color.FromName("Window")
or
cmbbox.ForeColor = Color.FromName("Window")

请帮忙

亲爱的亚当：

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我正在将我的组件设置为enable false。但是我想使其可见。您可以引用链接。这就是我想要的，但在VB.Net中：

要实现禁用组合框而不使其褪色，请首先将组合框的下拉样式更改为DropDownList，然后调整事件以实现目标

下面是一段代码，您可以通过它实现相同的功能：

Public Class Form1
Dim selectindex As Integer
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    ComboBox1.Items.Add("1")
    ComboBox1.Items.Add("2")
    ComboBox1.Items.Add("3")
    ComboBox1.Items.Add("4")
    selectindex = 3
    ComboBox1.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDownList
    ComboBox1.SelectedIndex = selectindex
End Sub

Private Sub ComboBox1_SelectionChangeCommitted(ByVal sender As Object, ByVal e As System.EventArgs) Handles ComboBox1.SelectionChangeCommitted
    ComboBox1.SelectedIndex = selectindex
End Sub
End Class

创建一个新的表单Form1并向表单中添加一个组合框，然后添加上面的代码以获得一个只读组合框。

看看哪个有一个只读组合框的解决方案，代码都是VB.NET

他们的代码版本如下。您需要将它放在您自己的类中，该类继承了

System.Windows.Forms.ComboBox

    Private _ReadOnly As Boolean = False

    Public Property [ReadOnly]() As Boolean    
        Get
            Return _ReadOnly
        End Get
        Set(ByVal Value As Boolean)
            _ReadOnly = Value
        End Set
    End Property

    Public Overrides Function PreProcessMessage(ByRef msg As Message) As Boolean
        'Prevent keyboard entry if control is ReadOnly  
        If _ReadOnly = True Then
            'Check if its a keydown message
            If msg.Msg = &H100 Then
                'Get the key that was pressed 
                Dim key As Int32 = msg.WParam.ToInt32
                'Ignore navigation keys 
                If key = Keys.Tab Or key = Keys.Left Or key = Keys.Right Then
                    'Do nothing    
                Else
                    Return True
                End If
            End If
        End If
        'Call base method so delegates receive event 
        Return MyBase.PreProcessMessage(msg)
    End Function

    Protected Overrides Sub WndProc(ByRef m As Message)
        'Prevent list displaying if ReadOnly
        If _ReadOnly = True Then
            If m.Msg = &H201 OrElse m.Msg = &H203 Then
                Return
            End If
        End If
        'Call base method so delegates receive event 
        MyBase.WndProc(m)
    End Sub

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不久前，我一直在寻找同样的方法，并最终完成了以下工作。你可能不喜欢，但我会分享它以防万一。我使用

TableLayoutPanel

在表单上排列控件，然后交换所需控件的位置

例如，我创建了以下项目：

表格布局面板1

（两列三行）

TextBox1

Read-only=True，BackColor=White

ComboBox1

Visible=False，DropDownStyle=DropDownList，FlatStyle=Popup

按钮1

（命名为要更改）

按钮2

（命名为完成）->Visible=False

这是我的密码：

Public Class Form1
    Private Sub SwapControls(tlp As TableLayoutPanel, ctr1 As Control, ctr2 As Control)
        Dim ctl1pos As TableLayoutPanelCellPosition = tlp.GetPositionFromControl(ctr1)
        ctr1.Visible = False
        tlp.SetCellPosition(ctr1, tlp.GetPositionFromControl(ctr2))
        ctr2.Visible = True
        tlp.SetCellPosition(ctr2, ctl1pos)
    End Sub

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        SwapControls(TableLayoutPanel1, TextBox1, ComboBox1)
        SwapControls(TableLayoutPanel1, Button1, Button2)
        Label1.Select()
    End Sub

    Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
        SwapControls(TableLayoutPanel1, ComboBox1, TextBox1)
        SwapControls(TableLayoutPanel1, Button2, Button1)
        Label1.Select()
    End Sub

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        Label1.Select()
        ComboBox1.SelectedIndex = 0

        TextBox1.Text = ComboBox1.SelectedItem
    End Sub

    Private Sub ComboBox1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles ComboBox1.SelectedIndexChanged
        TextBox1.Text = ComboBox1.SelectedItem
    End Sub
End Class

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您具体更改了组合框的哪些属性？实际上，当您禁用它时，它的外观就是这样。您是在修改

组合框的
已启用
还是
可见
属性？将
Visible
设置为false将不允许用户查看表单上的控件。将
Enabled
设置为false将使控件可见，但不可用并“灰显”。从你的帖子来看，问题并不完全清楚，但除非你有其他要求，否则我认为你不应该修改控件的颜色。你是否尝试过将你提到的任何项目转换为VB.Net？是的，我尝试过。但无法转换