Windows10下VB.NET如何获取标题栏颜色用于自定义无标题栏窗体

Windows 10的标题栏颜色属于系统主题着色色，需要调用DWM（桌面窗口管理器）API来获取，以下是具体实现方案：

1. 声明必要的Windows API函数 #

在窗体类顶部添加API声明，用于获取系统主题着色颜色：

Imports System.Runtime.InteropServices

Public Class Form1
    ' 调用DWM API获取系统着色颜色
    <DllImport("dwmapi.dll", PreserveSig:=False)>
    Private Shared Sub DwmGetColorizationColor(ByRef colorizationColor As UInteger, ByRef opaqueBlend As Boolean)
    End Sub

    ' 用于监听系统主题变化的API
    <DllImport("user32.dll", SetLastError:=True, CharSet:=CharSet.Auto)>
    Private Shared Function RegisterWindowMessage(ByVal lpString As String) As UInteger
    End Function

    ' 主题颜色变化的消息常量
    Private Const WM_DWMCOLORIZATIONCOLORCHANGED As UInteger = &H320
    Private _wmSysColorChange As UInteger

    ' 其他代码...
End Class

2. 编写获取标题栏颜色的方法 #

添加方法将API返回的数值转换为可直接使用的Color对象：

Private Function GetTitleBarColor() As Color
    Dim colorValue As UInteger
    Dim isOpaque As Boolean

    ' 调用API获取颜色值
    DwmGetColorizationColor(colorValue, isOpaque)

    ' 提取RGB通道值（Windows 10标题栏默认不透明，alpha设为255）
    Dim red As Integer = CInt((colorValue And &HFF))
    Dim green As Integer = CInt((colorValue And &HFF00) >> 8)
    Dim blue As Integer = CInt((colorValue And &HFF0000) >> 16)

    Return Color.FromArgb(255, red, green, blue)
End Function

3. 在窗体加载时设置Panel颜色 #

修改你的Form1_Load事件，添加颜色赋值代码：

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    Me.Text = ""
    Me.ControlBox = False
    Me.FormBorderStyle = FormBorderStyle.Sizable

    ' 将标题栏颜色应用到upper_panel
    upper_panel.BackColor = GetTitleBarColor()
End Sub

4. 监听主题变化自动更新颜色（可选） #

如果需要在用户切换系统亮/暗色主题时自动同步颜色，添加消息监听逻辑：

Protected Overrides Sub OnHandleCreated(e As EventArgs)
    MyBase.OnHandleCreated(e)
    ' 注册系统颜色变化的监听消息
    _wmSysColorChange = RegisterWindowMessage("WM_SYSCOLORCHANGE")
End Sub

Protected Overrides Sub WndProc(ByRef m As Message)
    MyBase.WndProc(m)

    ' 检测主题颜色变化消息，更新Panel颜色
    If m.Msg = WM_DWMCOLORIZATIONCOLORCHANGED OrElse m.Msg = _wmSysColorChange Then
        upper_panel.BackColor = GetTitleBarColor()
    End If
End Sub

注意事项 #

• 该方案仅适用于Windows平台，因为依赖Windows专属的DWM API
• 若使用.NET Core/.NET 5+，需确保项目引用System.Runtime.InteropServices包

内容的提问来源于stack exchange，提问作者Visula Kavinda