我正在为几个C# WinForms表单字段使用较暗的样式。特别是组合框类似于这个: 我正在使用来自此Stack答案的代码:Combobox borderstyle。不幸的是,我遇到了闪烁边框的问题。当我在组合框上移动鼠标时,它会快速闪烁出白色边框。是否有方法解决此问题?我尝试使用DoubleBuffer,但它并没有缓解该问题。
using System;
using System.Collections;
using System.Collections.Generic;
using System.ComponentModel;
using System.Windows.Forms;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Runtime.InteropServices;
namespace FlattenCombo
{
public class FlattenCombo : ComboBox
{
private Brush BorderBrush = new SolidBrush(SystemColors.WindowFrame);
private Brush ArrowBrush = new SolidBrush(SystemColors.ControlText);
private Brush DropButtonBrush = new SolidBrush(SystemColors.Control);
private Color _ButtonColor = SystemColors.Control;
public Color ButtonColor
{
get { return _ButtonColor; }
set
{
_ButtonColor = value;
DropButtonBrush = new SolidBrush(this.ButtonColor);
this.Invalidate();
}
}
private Color _borderColor = Color.Black;
private ButtonBorderStyle _borderStyle = ButtonBorderStyle.Solid;
//private static int WM_PAINT = 0x000F;
[Category("Appearance")]
public Color BorderColor
{
get { return _borderColor; }
set
{
_borderColor = value;
this.Invalidate(); // causes control to be redrawn
}
}
[Category("Appearance")]
public ButtonBorderStyle BorderStyle
{
get { return _borderStyle; }
set
{
_borderStyle = value;
this.Invalidate();
}
}
protected override void WndProc(ref Message m)
{
base.WndProc(ref m);
/*if (m.Msg == WM_PAINT)
{
Graphics g = Graphics.FromHwnd(Handle);
Rectangle bounds = new Rectangle(0, 0, Width, Height);
ControlPaint.DrawBorder(g, bounds, _borderColor, _borderStyle);
}*/
switch (m.Msg)
{
case 0xf:
//Paint the background. Only the borders
//will show up because the edit
//box will be overlayed
//Graphics g = Graphics.FromHwnd(Handle);
Graphics g = this.CreateGraphics();
Rectangle bounds = new Rectangle(0, 0, Width, Height);
ControlPaint.DrawBorder(g, bounds, _borderColor, _borderStyle);
//Pen p = new Pen(Color.White, 2);
//g.FillRectangle(BorderBrush, this.ClientRectangle);
//Draw the background of the dropdown button
Rectangle rect = new Rectangle(this.Width - 18, 0, 18, this.Height);
g.FillRectangle(DropButtonBrush, rect);
//Create the path for the arrow
System.Drawing.Drawing2D.GraphicsPath pth = new System.Drawing.Drawing2D.GraphicsPath();
PointF TopLeft = new PointF(this.Width - 13, (this.Height - 5) / 2);
PointF TopRight = new PointF(this.Width - 6, (this.Height - 5) / 2);
PointF Bottom = new PointF(this.Width - 9, (this.Height + 2) / 2);
pth.AddLine(TopLeft, TopRight);
pth.AddLine(TopRight, Bottom);
g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
//Determine the arrow's color.
if (this.DroppedDown)
{
ArrowBrush = new SolidBrush(SystemColors.HighlightText);
}
else
{
ArrowBrush = new SolidBrush(SystemColors.ControlText);
}
//Draw the arrow
g.FillPath(ArrowBrush, pth);
g.Dispose();
break;
}
}
//Override mouse and focus events to draw
//proper borders. Basically, set the color and Invalidate(),
//In general, Invalidate causes a control to redraw itself.
//#region "Mouse and focus Overrides"
protected override void OnMouseEnter(System.EventArgs e)
{
base.OnMouseEnter(e);
//BorderBrush = new SolidBrush(SystemColors.Highlight);
//EnableDoubleBuffering();
this.Invalidate();
}
protected override void OnMouseLeave(System.EventArgs e)
{
base.OnMouseLeave(e);
/*if (this.Focused)
return;*/
BorderBrush = new SolidBrush(SystemColors.WindowFrame);
//EnableDoubleBuffering();
this.Invalidate();
}
protected override void OnLostFocus(System.EventArgs e)
{
base.OnLostFocus(e);
//BorderBrush = new SolidBrush(SystemColors.Window);
//EnableDoubleBuffering();
this.Invalidate();
}
protected override void OnGotFocus(System.EventArgs e)
{
base.OnGotFocus(e);
BorderBrush = new SolidBrush(SystemColors.WindowFrame);
//EnableDoubleBuffering();
this.Invalidate();
}
protected override void OnMouseHover(System.EventArgs e)
{
base.OnMouseHover(e);
BorderBrush = new SolidBrush(SystemColors.WindowFrame);
//EnableDoubleBuffering();
this.Invalidate();
}
//#endregion
}
}