18

我在 C# 中使用 Windows 窗体,我需要使文本框的背景颜色透明。我有一个从 0 到 255 的轨迹栏,应该可以控制它,但我遇到了一些麻烦。我今天早些时候提出了一个问题,问了完全相同的问题,但没有成功。

这是我目前拥有的代码:

private void trackAlpha_ValueChanged(object sender, EventArgs e)
{
    newColor = Color.FromArgb(trackAlpha.Value, colorDialog.Color.R, colorDialog.Color.G, colorDialog.Color.B);
    colorDialog.Color = newColor; // The Windows dialog used to pick the colors
    colorPreview.BackColor = newColor; // Textbox that I'm setting the background color
}

问题是绝对没有任何事情发生。关于为什么这不起作用的任何想法?

在上一个问题上,这个好人说了一些关于SetStyle(ControlStyles.SupportsTransparentBackColor, true);,但我不知道我应该把它放在哪里。

4

6 回答 6

17

你需要尝试这样的事情。

添加一个新的用户控件,比如CustomTextBox并更改

public partial class CustomTextBox : UserControl

public partial class CustomTextBox : TextBox

然后,您将收到以下错误消息,指出未定义“AutoScaleMode”。删除 Designer.cs 类中的以下行。

this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;

对新添加的控件的构造函数进行如下更改。

public partial class CustomTextBox : TextBox
{
    public CustomTextBox()
    {
        InitializeComponent();
        SetStyle(ControlStyles.SupportsTransparentBackColor |
                 ControlStyles.OptimizedDoubleBuffer |
                 ControlStyles.AllPaintingInWmPaint |
                 ControlStyles.ResizeRedraw |
                 ControlStyles.UserPaint, true);
        BackColor = Color.Transparent;
    }
}

构建,关闭自定义控件设计器(如果打开),您将能够在任何其他控件或窗体上使用此控件。

从工具箱中删除它,如下所示 在此处输入图像描述

于 2013-04-17T03:19:31.047 回答
5

创建一个继承自 TextBox 的新控件,在构造函数中设置样式以允许透明。然后使用您的新控件而不是 TextBox

在您的构造函数中执行此操作:

this.SetStyle(ControlStyles.SupportsTransparentBackColor, true);

这将允许您的新控件具有透明的背景颜色。

您可以在此处阅读有关控件样式的更多信息;MSDN:Control Styles,这也可能有所帮助;使用 Visual C# 从 Windows 窗体控件继承

于 2013-04-17T02:44:21.707 回答
5

我从不喜欢为此制作自己的继承控件。所以我为私有 SetStyle 函数做了一个包装函数。

尝试使用它而不是创建自己的类?

public static bool SetStyle(Control c, ControlStyles Style, bool value)
{
    bool retval = false;
    Type typeTB = typeof(Control);
    System.Reflection.MethodInfo misSetStyle = typeTB.GetMethod("SetStyle", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance);
    if (misSetStyle != null && c != null) { misSetStyle.Invoke(c, new object[] { Style, value }); retval = true; }
    return retval;
}

bool itWorked = SetStyle(myControl, ControlStyles.SupportsTransparentBackColor, true);

于 2014-02-19T15:47:27.257 回答
1

很抱歉发现旧帖子,但是,现在一直在寻找几天来解决这个可怕的文本框不透明问题的解决方案!!!(令人惊讶的是,MSAccess 有一个检查状态来显示透明度!)

无论如何,我已经建立了一个 VB 解决方法,但是,它非常粗糙,虽然可能对很多人有所帮助,但也希望从更核心的人那里获得任何见解......

它基本上使用文本框,然后将其调整大小并替换为标签(因此现在代表一个透明的“出现”文本框。还有其他一些事情,例如在单行文本框上按 enter 时停止哔哔声。

要使用 - 创建一个新类并将所有代码粘贴到顶部,这应该创建两个自定义对象( CTextBox 和 CLabel ) - 您只需要在表单设计中使用 CTEXTBOX。

轻松转换为 C,如果那是您的语言,但如果有任何建议,请告诉我?

Imports System.ComponentModel

Public Class CTextBox
Inherits TextBox
Dim _zUseEnterAsTab As Boolean = True
Dim _zUseTransparent As Boolean = False
Dim _zUseTransparentColor As Color = Color.Transparent
Dim _zUseTransparentBorderColor As Color = Color.Gray
<Description("Use the Enter Key as Tab (Stops Beeps) only for Single line TextBox"), Category("CTextBox")> _
Public Property zUseEnterAsTab() As Boolean
    Get
        Return _zUseEnterAsTab
    End Get
    Set(value As Boolean)
        _zUseEnterAsTab = value
        Me.Invalidate()
    End Set
End Property
<Description("Use Transparent TextBox"), Category("CTextBox")> _
    Public Property zUseTransparent() As Boolean
    Get
        Return _zUseTransparent
    End Get
    Set(value As Boolean)
        _zUseTransparent = value
        Me.Invalidate()
    End Set
End Property
<Description("Change the transparency to ANY color or shade or Alpha"), Category("CTextBox")> _
Public Property zUseTransparentColor() As Color
    Get
        Return _zUseTransparentColor
    End Get
    Set(value As Color)
        _zUseTransparentColor = value
        Me.Invalidate()
    End Set
End Property
<Description("Border color of the texbox when transparency used"), Category("CTextBox")> _
    Public Property zUseTransparentBorderColor() As Color
    Get
        Return _zUseTransparentBorderColor
    End Get
    Set(value As Color)
        _zUseTransparentBorderColor = value
        Me.Invalidate()
    End Set
End Property
Protected Overrides Sub OnCreateControl()
    'Again for my benifit - there may be other ways to force the transparency 
    'code at form / event startup, but this is the way i chose, any advice
    'or alternatives would be great!! :)
    If Not DesignMode Then
        'Basically don't do in design mode!
        If _zUseTransparent Then
            'Added to handle the event of textbox dissabled
            If Me.Enabled Then
                CreateMyLabel(Me)
                MakeLabelVisible(foundLabel, Me)
            End If
        End If
    End If
    MyBase.OnCreateControl()
End Sub
Protected Overrides Sub OnKeyPress(e As KeyPressEventArgs)
    If MyBase.Multiline = True Then
        MyBase.OnKeyPress(e)
    Else
        If e.KeyChar = Chr(Keys.Enter) Then
            e.Handled = True
            If zUseEnterAsTab = True Then SendKeys.Send("{tab}")
            MyBase.OnKeyPress(e)
        End If
    End If
End Sub
Protected Overrides Sub OnLeave(e As EventArgs)
    If _zUseTransparent Then
        CreateMyLabel(Me)
        MakeLabelVisible(foundLabel, Me)
    End If
    MyBase.OnLeave(e)
End Sub
Protected Overrides Sub OnEnter(e As EventArgs)
    If _zUseTransparent Then
        CreateMyLabel(Me)
        MakeTextBoxVisible(foundLabel, Me)
    End If
    MyBase.OnEnter(e)
End Sub
Dim foundLabel As CLabel = Nothing
Sub CreateMyLabel(_TxtBox As CTextBox)
    foundLabel = Nothing
    Dim l As CLabel
    If GetMyLabel("L_" & Me.Name, Me) Then
        l = foundLabel
        If Not l.Name = "L_" & Me.Name Then
            MsgBox("L_" & Me.Name)
        End If
        l.Font = _TxtBox.Font
        l.Text = _TxtBox.Text
        l.BorderColor = _zUseTransparentBorderColor
        l.BackColor = _zUseTransparentColor
        l.BorderStyle = Windows.Forms.BorderStyle.None 'Handled by paint event
    Else
        l = New CLabel
        l.Name = "L_" & _TxtBox.Name
        l.BorderColor = _zUseTransparentBorderColor
        l.BackColor = _zUseTransparentColor
        l.Size = _TxtBox.Size
        l.BorderStyle = Windows.Forms.BorderStyle.None 'Handled by paint event
        l.AutoSize = False
        l.Font = _TxtBox.Font
        l.Location = _TxtBox.Location
        l.Text = _TxtBox.Text
        l.Anchor = _TxtBox.Anchor
        _TxtBox.Parent.Controls.Add(l)
        foundLabel = l
    End If
End Sub
Function GetMyLabel(_LabelName As String, _TxtBox As CTextBox) As Boolean
    For Each ctl As Control In _TxtBox.Parent.Controls
        If ctl.Name = _LabelName Then
            foundLabel = ctl
            Return True
        End If
    Next
    Return False
End Function
Private Sub MakeLabelVisible(_Label As CLabel, _TxtBox As CTextBox)
    _Label.Location = _TxtBox.Location
    _Label.Anchor = _TxtBox.Anchor
    _Label.Size = _TxtBox.Size
    _TxtBox.Size = New Size(0, 0)
    _TxtBox.Anchor = AnchorStyles.None
End Sub
Private Sub MakeTextBoxVisible(_Label As CLabel, _TxtBox As CTextBox)
    _TxtBox.Location = _Label.Location
    _TxtBox.Anchor = _Label.Anchor
    _TxtBox.Size = _Label.Size
    _Label.Size = New Size(0, 0)
    _Label.Anchor = AnchorStyles.None
End Sub
End Class

Public Class CLabel
Inherits Label
Public BorderColor As Color = Color.Gray
Sub New()
    MyBase.FlatStyle = Windows.Forms.FlatStyle.Standard
    'Added padding as labels shifted text upwards
    'NOT tested on all fonts etc, purely for my sources
    MyBase.Padding = New Padding(0, 3, 0, 0)
End Sub
Protected Overrides Sub OnMouseDown(e As MouseEventArgs)
    Dim _TxtBox As CTextBox = Nothing
    Dim _TxtBoxName As String = Microsoft.VisualBasic.Right(Me.Name, Len(Me.Name) - 2)
    For Each elem As Control In Me.Parent.Controls
        If elem.Name = _TxtBoxName Then
            _TxtBox = elem
            Exit For
        End If
    Next
    _TxtBox.Select()
    MyBase.OnMouseDown(e)
End Sub
Protected Overrides Sub OnMouseEnter(e As EventArgs)
    Cursor = Cursors.IBeam
    MyBase.OnMouseEnter(e)
End Sub
Protected Overrides Sub OnMouseLeave(e As EventArgs)
    Cursor = Cursors.Default
    MyBase.OnMouseLeave(e)
End Sub
Protected Overrides Sub OnPaint(e As PaintEventArgs)
    MyBase.OnPaint(e)
    ControlPaint.DrawBorder(e.Graphics, Me.DisplayRectangle, Color.Gray, ButtonBorderStyle.Solid)
End Sub
Private Sub MakeLabelVisible(_Label As CLabel, _TxtBox As CTextBox)
    _Label.Size = _TxtBox.Size
    _TxtBox.Size = New Size(0, 0)
    _Label.Anchor = _TxtBox.Anchor
    _TxtBox.Anchor = AnchorStyles.None
End Sub
Private Sub MakeTextBoxVisible(_Label As CLabel, _TxtBox As CTextBox)
    _TxtBox.Size = _Label.Size
    _Label.Size = New Size(0, 0)
    _TxtBox.Anchor = _Label.Anchor
    _TxtBox.Anchor = AnchorStyles.None
End Sub
End Class
于 2014-09-03T14:53:58.990 回答
1

就这一行,它对我来说非常有效!

textBox1.BackColor = this.BackColor;

来源:https ://www.codegrepper.com/code-examples/csharp/set+textbox+colour+to+transparent+c%23

于 2020-10-27T23:31:42.027 回答
-3
this.SetStyle(ControlStyles.SupportsTransparentBackColor, true);
于 2015-12-11T01:25:10.780 回答