c# - 向工具条进度条添加文本

Question

我正在尝试向 Tool Strip Progress Bar 添加一些文本但到目前为止我一直没有成功，这是我找到的一些代码 HERE :

private void pbPrecentage(ToolStripProgressBar pb)
{
    ProgressBar p = new ProgressBar();

    int percent = (int)(((double)(pb.Value - pb.Minimum) /
    (double)(pb.Maximum - pb.Minimum)) * 100);
    using (Graphics gr = pb.CreateGraphics())
    {
        gr.DrawString(percent.ToString() + "%",
            SystemFonts.DefaultFont,
            Brushes.Black,
            new PointF(pb.Width / 2 - (gr.MeasureString(percent.ToString() + "%",
                SystemFonts.DefaultFont).Width / 2.0F),
            pb.Height / 2 - (gr.MeasureString(percent.ToString() + "%",
                SystemFonts.DefaultFont).Height / 2.0F)));
    }
}

问题是 Tool Strip Progress Bar 没有 CreateGraphics 方法。所以我想知道是否有人能够成功地将文本添加到工具条进度条。

更新

好的，ToolStripProgressBar 似乎有一个进度条属性，该属性又具有 CreateGraphics 方法，但现在的问题是文本值在闪烁，我该如何解决这个问题？这是修改后的代码:

private void pbPrecentage(ToolStripProgressBar pb)
{
    int percent = (int)(((double)(pb.Value - pb.Minimum) /
    (double)(pb.Maximum - pb.Minimum)) * 100);

    using (Graphics gr = pb.ProgressBar.CreateGraphics())
    {
        gr.DrawString(percent.ToString() + "%",
            SystemFonts.DefaultFont,
            Brushes.Black,
            new PointF(pb.Width / 2 - (gr.MeasureString(percent.ToString() + "%",
                SystemFonts.DefaultFont).Width / 2.0F),
            pb.Height / 2 - (gr.MeasureString(percent.ToString() + "%",
                SystemFonts.DefaultFont).Height / 2.0F)));
    }
}

Answer 1

您遇到了一个与基于 GDI+ 的 Windows 窗体有关的非常常见的问题。用于绘制控件(以及图形等用户绘图上下文)的双缓冲标准设置已关闭。所以只需在您的表单中添加几行代码:

public Form1()
{
//Activate Double Buffering for all kind of drawing within your form
this.SetStyle(ControlStyles.AllPaintingInWmPaint | ControlStyles.UserPaint | ControlStyles.DoubleBuffer, true);
}

如果你还想获得更好的图形，那么你还应该为你的绘图上下文使用 SmoothingMode:

private void pbPrecentage(ToolStripProgressBar pb)
{
    int percent = (int)(((double)(pb.Value - pb.Minimum) /
    (double)(pb.Maximum - pb.Minimum)) * 100);

    using (Graphics gr = pb.ProgressBar.CreateGraphics())
    {
        //Switch to Antialiased drawing for better (smoother) graphic results
        gr.SmoothingMode = SmoothingMode.AntiAlias;
        gr.DrawString(percent.ToString() + "%",
            SystemFonts.DefaultFont,
            Brushes.Black,
            new PointF(pb.Width / 2 - (gr.MeasureString(percent.ToString() + "%",
                SystemFonts.DefaultFont).Width / 2.0F),
            pb.Height / 2 - (gr.MeasureString(percent.ToString() + "%",
                SystemFonts.DefaultFont).Height / 2.0F)));
    }
}