WinForm透明背景文字轮廓有窗体背景色

Question

现在我遇到了透明键的问题。我将所需的表单（希望显示为对话框）TransparencyKey 设置为 Color.White 和 BackColor Color.White。该表单使用的文本 ForeColor 是 ControlText.

后台应用程序具有 white/control 背景颜色时的外观（

当对话框显示在应用程序顶部时，看起来像：

我可以看到显示透明背景的窗体，当背景色为白色时也很好看。但是当背景颜色是深色主题颜色（黑色，灰色等）时，它看起来很糟糕并且有一些白色轮廓。我应该怎么做才能防止这种情况发生？

编辑：很抱歉缺少信息。表单中显示的文本是 Label 对象。对于设置 TransparencyKey、BackColor 等属性的代码在 designer.cs 中。这里是设计师和.cs的代码。

ReaderInitializer.cs

public partial class ReaderInitializer : Form
    {
        Reader _reader;

        /// <summary>
        /// Occur when being notify to close this screen.
        /// </summary>
        private event EventHandler NotifyClose;

        public ReaderInitializer()
        {
            InitializeComponent();
            NotifyClose += OnClose;
            try
            {
                lbl_Message.Text = "Please insert the card.";
                pb_Icon.Image = new Bitmap($@"{ProgramInfo.RootPath}\img\init\load.png");
            }
            catch (Exception e)
            {
                SystemLog.Write(e);
            }
        }

        public void SetReaderNotify(Reader reader)
        {
            reader.MapSuccess += ReaderInitSuccess;
            _reader = reader;
        }

        private void ReaderInitSuccess(object sender, MapSuccessEventArgs e)
        {
            Action uiAction = () =>
            {
                lbl_Message.Text = e.Message;
                pb_Icon.Image = e.DisplayImage;
                if (_reader != null)
                    _reader.MapSuccess -= ReaderInitSuccess;
            };

            if (InvokeRequired)
            {
                Invoke((MethodInvoker)delegate { uiAction(); });
            }
            else
            {
                uiAction();
            }

            NotifyClose?.Invoke(this, new EventArgs());
        }

        private void OnClose(object sender, EventArgs e)
        {
            // Suspecting causing hang when closing dialog.
            Task.Delay(3000).Wait();
            Close();
        }
    }

ReaderInitializer.Designer.cs

        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
        private void InitializeComponent()
        {
            this.tlp_Icon = new System.Windows.Forms.TableLayoutPanel();
            this.pn_Header = new System.Windows.Forms.Panel();
            this.pn_Footer = new System.Windows.Forms.Panel();
            this.pn_Message = new System.Windows.Forms.Panel();
            this.pb_Icon = new System.Windows.Forms.PictureBox();
            this.lbl_Message = new System.Windows.Forms.Label();
            this.tlp_Icon.SuspendLayout();
            this.pn_Message.SuspendLayout();
            ((System.ComponentModel.ISupportInitialize)(this.pb_Icon)).BeginInit();
            this.SuspendLayout();
            // 
            // tlp_Icon
            // 
            this.tlp_Icon.ColumnCount = 3;
            this.tlp_Icon.ColumnStyles.Add(new System.Windows.Forms.ColumnStyle(System.Windows.Forms.SizeType.Percent, 15F));
            this.tlp_Icon.ColumnStyles.Add(new System.Windows.Forms.ColumnStyle(System.Windows.Forms.SizeType.Percent, 70F));
            this.tlp_Icon.ColumnStyles.Add(new System.Windows.Forms.ColumnStyle(System.Windows.Forms.SizeType.Percent, 15F));
            this.tlp_Icon.Controls.Add(this.pb_Icon, 1, 0);
            this.tlp_Icon.Location = new System.Drawing.Point(0, 42);
            this.tlp_Icon.Margin = new System.Windows.Forms.Padding(0);
            this.tlp_Icon.Name = "tlp_Icon";
            this.tlp_Icon.RowCount = 1;
            this.tlp_Icon.RowStyles.Add(new System.Windows.Forms.RowStyle(System.Windows.Forms.SizeType.Percent, 100F));
            this.tlp_Icon.Size = new System.Drawing.Size(800, 258);
            this.tlp_Icon.TabIndex = 0;
            // 
            // pn_Header
            // 
            this.pn_Header.Dock = System.Windows.Forms.DockStyle.Top;
            this.pn_Header.Location = new System.Drawing.Point(0, 0);
            this.pn_Header.Margin = new System.Windows.Forms.Padding(0);
            this.pn_Header.Name = "pn_Header";
            this.pn_Header.Size = new System.Drawing.Size(800, 42);
            this.pn_Header.TabIndex = 1;
            // 
            // pn_Footer
            // 
            this.pn_Footer.Dock = System.Windows.Forms.DockStyle.Bottom;
            this.pn_Footer.Location = new System.Drawing.Point(0, 400);
            this.pn_Footer.Margin = new System.Windows.Forms.Padding(0);
            this.pn_Footer.Name = "pn_Footer";
            this.pn_Footer.Size = new System.Drawing.Size(800, 50);
            this.pn_Footer.TabIndex = 2;
            // 
            // pn_Message
            // 
            this.pn_Message.Controls.Add(this.lbl_Message);
            this.pn_Message.Dock = System.Windows.Forms.DockStyle.Bottom;
            this.pn_Message.Location = new System.Drawing.Point(0, 300);
            this.pn_Message.Margin = new System.Windows.Forms.Padding(0);
            this.pn_Message.Name = "pn_Message";
            this.pn_Message.Size = new System.Drawing.Size(800, 100);
            this.pn_Message.TabIndex = 3;
            // 
            // pb_Icon
            // 
            this.pb_Icon.Dock = System.Windows.Forms.DockStyle.Fill;
            this.pb_Icon.Location = new System.Drawing.Point(120, 0);
            this.pb_Icon.Margin = new System.Windows.Forms.Padding(0);
            this.pb_Icon.Name = "pb_Icon";
            this.pb_Icon.Size = new System.Drawing.Size(560, 258);
            this.pb_Icon.SizeMode = System.Windows.Forms.PictureBoxSizeMode.Zoom;
            this.pb_Icon.TabIndex = 0;
            this.pb_Icon.TabStop = false;
            // 
            // lbl_Message
            // 
            this.lbl_Message.Dock = System.Windows.Forms.DockStyle.Fill;
            this.lbl_Message.Font = new System.Drawing.Font("Roboto", 18F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((byte)(0)));
            this.lbl_Message.Location = new System.Drawing.Point(0, 0);
            this.lbl_Message.Margin = new System.Windows.Forms.Padding(0);
            this.lbl_Message.Name = "lbl_Message";
            this.lbl_Message.Size = new System.Drawing.Size(800, 100);
            this.lbl_Message.TabIndex = 0;
            this.lbl_Message.Text = "...";
            this.lbl_Message.TextAlign = System.Drawing.ContentAlignment.MiddleCenter;
            // 
            // ReaderInitializer
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.BackColor = System.Drawing.Color.White;
            this.ClientSize = new System.Drawing.Size(800, 450);
            this.Controls.Add(this.pn_Message);
            this.Controls.Add(this.pn_Footer);
            this.Controls.Add(this.pn_Header);
            this.Controls.Add(this.tlp_Icon);
            this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.None;
            this.Name = "ReaderInitializer";
            this.StartPosition = System.Windows.Forms.FormStartPosition.CenterScreen;
            this.Text = "Guest Service Station";
            this.TransparencyKey = System.Drawing.Color.White;
            this.tlp_Icon.ResumeLayout(false);
            this.pn_Message.ResumeLayout(false);
            ((System.ComponentModel.ISupportInitialize)(this.pb_Icon)).EndInit();
            this.ResumeLayout(false);

        }

Answer 1

您遇到这个问题：

我已将表单的 BackColor 和 TransparencyKey 更改为紫红色，并将 Label.ForeColor 更改为灰色。请注意 TransparencyKey 是如何勾勒文本轮廓的。 Here 是一个很好的解释。

建议的修复 - 上面评论 - 是自己绘制字符串，Gdi+ 方法通过 TextRenderingHint.SingleBitPerPixelGridFit 提示控制字符串渲染质量，这为这个问题提供了更好的抗锯齿。

// +
// System.Drawing.Text;

private void lbl_Message_Paint(object sender, PaintEventArgs e)
{
    e.Graphics.Clear(lbl_Message.BackColor);

    using (var sf = new StringFormat())
    using (var br = new SolidBrush(lbl_Message.ForeColor))
    {
        sf.Alignment = sf.LineAlignment = StringAlignment.Center;
        e.Graphics.TextRenderingHint = TextRenderingHint.SingleBitPerPixelGridFit;
        e.Graphics.DrawString(lbl_Message.Text, lbl_Message.Font, br,
            lbl_Message.ClientRectangle, sf);
    }
}

您将获得：

WinForm透明背景文字轮廓有窗体背景色

WinForm transparent background text outline have the form background color

c#

winforms