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using System; namespace LC.Fun { /// <summary>Panel扩展 带圆角，颜色渐变</summary> [System.Drawing.ToolboxBitmapAttribute(typeof(System.Windows.Forms.Panel))] public class RoundPanel : System.Windows.Forms.Panel { /// <summary>渐变的方向</summary> public enum LinearGradientMode { Horizontal = 0, Vertical = 1, ForwardDiagonal = 2, BackwardDiagonal = 3, None = 4 } /// <summary> /// 圆角的位置 /// </summary> [FlagsAttribute()] public enum CornerCurveMode { None = 0, TopLeft = 1, TopRight = 2, TopLeft_TopRight = 3, BottomLeft = 4, TopLeft_BottomLeft = 5, TopRight_BottomLeft = 6, TopLeft_TopRight_BottomLeft = 7, BottomRight = 8, BottomRight_TopLeft = 9, BottomRight_TopRight = 10, BottomRight_TopLeft_TopRight = 11, BottomRight_BottomLeft = 12, BottomRight_TopLeft_BottomLeft = 13, BottomRight_TopRight_BottomLeft = 14, All = 15 } // Fields private System.Drawing.Color _BackColour1 = System.Drawing.SystemColors.Window; private System.Drawing.Color _BackColour2 = System.Drawing.SystemColors.Window; private LinearGradientMode _GradientMode = LinearGradientMode.None; private System.Windows.Forms.BorderStyle _BorderStyle = System.Windows.Forms.BorderStyle.None; private System.Drawing.Color _BorderColour = System.Drawing.SystemColors.WindowFrame; private int _BorderWidth = 1; private int _Curvature = 0; // Properties // Shadow the Backcolor property so that the base class will still render with a transparent backcolor private CornerCurveMode _CurveMode = CornerCurveMode.All; [System.ComponentModel.DefaultValueAttribute(typeof(System.Drawing.Color), "Window"), System.ComponentModel.CategoryAttribute("自定义cx"), System.ComponentModel.DescriptionAttribute("背景色1")] public new System.Drawing.Color BackColor { get { return this._BackColour1; } set { this._BackColour1 = value; if (this.DesignMode == true) { this.Invalidate(); } } } [System.ComponentModel.DefaultValueAttribute(typeof(System.Drawing.Color), "Window"), System.ComponentModel.CategoryAttribute("自定义cx"), System.ComponentModel.DescriptionAttribute("背景色2")] public System.Drawing.Color BackColor2 { get { return this._BackColour2; } set { this._BackColour2 = value; if (this.DesignMode == true) { this.Invalidate(); } } } [System.ComponentModel.DefaultValueAttribute(typeof(LinearGradientMode), "None"), System.ComponentModel.CategoryAttribute("自定义cx"), System.ComponentModel.DescriptionAttribute("颜色渐变的方向")] public LinearGradientMode GradientMode { get { return this._GradientMode; } set { this._GradientMode = value; if (this.DesignMode == true) { this.Invalidate(); } } } [System.ComponentModel.DefaultValueAttribute(typeof(System.Windows.Forms.BorderStyle), "None"), System.ComponentModel.CategoryAttribute("自定义cx"), System.ComponentModel.DescriptionAttribute("边框的样式")] public new System.Windows.Forms.BorderStyle BorderStyle { get { return this._BorderStyle; } set { this._BorderStyle = value; if (this.DesignMode == true) { this.Invalidate(); } } } [System.ComponentModel.DefaultValueAttribute(typeof(System.Drawing.Color), "WindowFrame"), System.ComponentModel.CategoryAttribute("自定义cx"), System.ComponentModel.DescriptionAttribute("边框的颜色")] public System.Drawing.Color BorderColor { get { return this._BorderColour; } set { this._BorderColour = value; if (this.DesignMode == true) { this.Invalidate(); } } } [System.ComponentModel.DefaultValueAttribute(typeof(int), "1"), System.ComponentModel.CategoryAttribute("自定义cx"), System.ComponentModel.DescriptionAttribute("边框大小")] public int BorderWidth { get { return this._BorderWidth; } set { this._BorderWidth = value; if (this.DesignMode == true) { this.Invalidate(); } } } [System.ComponentModel.DefaultValueAttribute(typeof(int), "0"), System.ComponentModel.CategoryAttribute("自定义cx"), System.ComponentModel.DescriptionAttribute("圆角大小")] public int Curvature { get { return this._Curvature; } set { this._Curvature = value; if (this.DesignMode == true) { this.Invalidate(); } } } [System.ComponentModel.DefaultValueAttribute(typeof(CornerCurveMode), "All"), System.ComponentModel.CategoryAttribute("自定义cx"), System.ComponentModel.DescriptionAttribute("圆角的位置")] public CornerCurveMode CurveMode { get { return this._CurveMode; } set { this._CurveMode = value; if (this.DesignMode == true) { this.Invalidate(); } } } private int adjustedCurve { get { int curve = 0; if (!(this._CurveMode == CornerCurveMode.None)) { if (this._Curvature > (this.ClientRectangle.Width / 2)) { curve = DoubleToInt(this.ClientRectangle.Width / 2); } else { curve = this._Curvature; } if (curve > (this.ClientRectangle.Height / 2)) { curve = DoubleToInt(this.ClientRectangle.Height / 2); } } return curve; } } public RoundPanel() : base() { this.SetDefaultControlStyles(); this.customInitialisation(); } private void SetDefaultControlStyles() { this.SetStyle(System.Windows.Forms.ControlStyles.DoubleBuffer, true); this.SetStyle(System.Windows.Forms.ControlStyles.AllPaintingInWmPaint, false); this.SetStyle(System.Windows.Forms.ControlStyles.ResizeRedraw, true); this.SetStyle(System.Windows.Forms.ControlStyles.UserPaint, true); this.SetStyle(System.Windows.Forms.ControlStyles.SupportsTransparentBackColor, true); } private void customInitialisation() { this.SuspendLayout(); base.BackColor = System.Drawing.Color.Transparent; this.BorderStyle = System.Windows.Forms.BorderStyle.None; this.ResumeLayout(false); } protected override void OnPaintBackground(System.Windows.Forms.PaintEventArgs pevent) { base.OnPaintBackground(pevent); pevent.Graphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias; System.Drawing.Drawing2D.GraphicsPath graphPath; graphPath = this.GetPath(); // Create Gradient Brush (Cannot be width or height 0) System.Drawing.Drawing2D.LinearGradientBrush filler; System.Drawing.Rectangle rect = this.ClientRectangle; if (this.ClientRectangle.Width == 0) { rect.Width += 1; } if (this.ClientRectangle.Height == 0) { rect.Height += 1; } if (this._GradientMode == LinearGradientMode.None) { filler = new System.Drawing.Drawing2D.LinearGradientBrush(rect, this._BackColour1, this._BackColour1, System.Drawing.Drawing2D.LinearGradientMode.Vertical); } else { filler = new System.Drawing.Drawing2D.LinearGradientBrush(rect, this._BackColour1, this._BackColour2, ((System.Drawing.Drawing2D.LinearGradientMode)this._GradientMode)); } pevent.Graphics.FillPath(filler, graphPath); filler.Dispose(); if (this._BorderStyle == System.Windows.Forms.BorderStyle.FixedSingle) { System.Drawing.Pen borderPen = new System.Drawing.Pen(this._BorderColour, this._BorderWidth); pevent.Graphics.DrawPath(borderPen, graphPath); borderPen.Dispose(); } else if (this._BorderStyle == System.Windows.Forms.BorderStyle.Fixed3D) { DrawBorder3D(pevent.Graphics, this.ClientRectangle); } else if (this._BorderStyle == System.Windows.Forms.BorderStyle.None) { } filler.Dispose(); graphPath.Dispose(); } protected System.Drawing.Drawing2D.GraphicsPath GetPath() { System.Drawing.Drawing2D.GraphicsPath graphPath = new System.Drawing.Drawing2D.GraphicsPath(); if (this._BorderStyle == System.Windows.Forms.BorderStyle.Fixed3D) { graphPath.AddRectangle(this.ClientRectangle); } else { try { int curve = 0; System.Drawing.Rectangle rect = this.ClientRectangle; int offset = 0; if (this._BorderStyle == System.Windows.Forms.BorderStyle.FixedSingle) { if (this._BorderWidth > 1) { offset = DoubleToInt(this.BorderWidth / 2); } curve = this.adjustedCurve; } else if (this._BorderStyle == System.Windows.Forms.BorderStyle.Fixed3D) { } else if (this._BorderStyle == System.Windows.Forms.BorderStyle.None) { curve = this.adjustedCurve; } if (curve == 0) { graphPath.AddRectangle(System.Drawing.Rectangle.Inflate(rect, -offset, -offset)); } else { int rectWidth = rect.Width - 1 - offset; int rectHeight = rect.Height - 1 - offset; int curveWidth = 1; if ((this._CurveMode & CornerCurveMode.TopRight) != 0) { curveWidth = (curve * 2); } else { curveWidth = 1; } graphPath.AddArc(rectWidth - curveWidth, offset, curveWidth, curveWidth, 270, 90); if ((this._CurveMode & CornerCurveMode.BottomRight) != 0) { curveWidth = (curve * 2); } else { curveWidth = 1; } graphPath.AddArc(rectWidth - curveWidth, rectHeight - curveWidth, curveWidth, curveWidth, 0, 90); if ((this._CurveMode & CornerCurveMode.BottomLeft) != 0) { curveWidth = (curve * 2); } else { curveWidth = 1; } graphPath.AddArc(offset, rectHeight - curveWidth, curveWidth, curveWidth, 90, 90); if ((this._CurveMode & CornerCurveMode.TopLeft) != 0) { curveWidth = (curve * 2); } else { curveWidth = 1; } graphPath.AddArc(offset, offset, curveWidth, curveWidth, 180, 90); graphPath.CloseFigure(); } } catch (System.Exception) { graphPath.AddRectangle(this.ClientRectangle); } } return graphPath; } public static void DrawBorder3D(System.Drawing.Graphics graphics, System.Drawing.Rectangle rectangle) { graphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.Default; graphics.DrawLine(System.Drawing.SystemPens.ControlDark, rectangle.X, rectangle.Y, rectangle.Width - 1, rectangle.Y); graphics.DrawLine(System.Drawing.SystemPens.ControlDark, rectangle.X, rectangle.Y, rectangle.X, rectangle.Height - 1); graphics.DrawLine(System.Drawing.SystemPens.ControlDarkDark, rectangle.X + 1, rectangle.Y + 1, rectangle.Width - 1, rectangle.Y + 1); graphics.DrawLine(System.Drawing.SystemPens.ControlDarkDark, rectangle.X + 1, rectangle.Y + 1, rectangle.X + 1, rectangle.Height - 1); graphics.DrawLine(System.Drawing.SystemPens.ControlLight, rectangle.X + 1, rectangle.Height - 2, rectangle.Width - 2, rectangle.Height - 2); graphics.DrawLine(System.Drawing.SystemPens.ControlLight, rectangle.Width - 2, rectangle.Y + 1, rectangle.Width - 2, rectangle.Height - 2); graphics.DrawLine(System.Drawing.SystemPens.ControlLightLight, rectangle.X, rectangle.Height - 1, rectangle.Width - 1, rectangle.Height - 1); graphics.DrawLine(System.Drawing.SystemPens.ControlLightLight, rectangle.Width - 1, rectangle.Y, rectangle.Width - 1, rectangle.Height - 1); } public static int DoubleToInt(double value) { return System.Decimal.ToInt32(System.Decimal.Floor(System.Decimal.Parse((value).ToString()))); } } }