using System.ComponentModel;
using System.Drawing;
using System.Windows.Forms;

namespace JinYuan.ControlLib
{
    public partial class CheckBoxExt : CheckBox
    {
        public CheckBoxExt()
        {
            InitializeComponent();

            _format.LineAlignment = StringAlignment.Center;
            _format.Alignment = StringAlignment.Center;


            //设置控件样式，去除缓冲
            this.SetStyle(ControlStyles.AllPaintingInWmPaint, true);
            this.SetStyle(ControlStyles.DoubleBuffer, true);
            this.SetStyle(ControlStyles.ResizeRedraw, true);
            this.SetStyle(ControlStyles.Selectable, true);
            this.SetStyle(ControlStyles.SupportsTransparentBackColor, true);
        }

        private StringFormat _format = new StringFormat();



        private int defultCheckButtonWidth = 20;
        [Browsable(true)]//是否可见
        [Category("自定义属性")] //类别
        [Description("设置或显示标题名称")]
        public int DefultCheckButtonWidth
        {
            get { return defultCheckButtonWidth; }
            set { defultCheckButtonWidth = value; }
        }

        private Color checkColor = Color.FromArgb(3, 25, 66);
        [Browsable(true)]//是否可见
        [Category("自定义属性")] //类别
        [Description("设置或显示选中颜色")]
        public Color CheckColor
        {
            get { return checkColor; }
            set
            {
                checkColor = value;
                this.Invalidate();
            }
        }

        private Color checkBackColor = Color.White;
        [Browsable(true)]//是否可见
        [Category("自定义属性")] //类别
        [Description("设置或显示选中框背景颜色")]
        public Color CheckBackColor
        {
            get { return checkBackColor; }
            set
            {
                checkBackColor = value;
                this.Invalidate();
            }
        }


        protected override void OnPaint(PaintEventArgs e)
        {
            base.OnPaint(e);
            base.OnPaintBackground(e);

            Graphics g = e.Graphics;
            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;
            g.TextRenderingHint = System.Drawing.Text.TextRenderingHint.ClearTypeGridFit;

            Rectangle checkRec;
            Rectangle textRec;

            CalculatorRec(out checkRec, out textRec);

            SolidBrush solidBrush = new SolidBrush(CheckBackColor);
            g.FillRectangle(solidBrush, checkRec);

            Pen pen = new Pen(Color.LightGray);
            g.DrawRectangle(pen, checkRec);

            if (this.CheckState == CheckState.Checked)
            {
                //画勾选
                DrawCheckFlag(g, checkRec, checkColor);
            }

            //绘制文本
            g.DrawString(this.Text, this.Font, new SolidBrush(this.ForeColor), textRec, this._format);
        }


        /// <summary>
        /// 计算矩形
        /// </summary>
        /// <param name="checkRec"></param>
        /// <param name="textRec"></param>
        private void CalculatorRec(out Rectangle checkRec, out Rectangle textRec)
        {
            checkRec = new Rectangle(3, (this.Height - defultCheckButtonWidth) / 2, defultCheckButtonWidth,
                defultCheckButtonWidth);

            textRec = new Rectangle(checkRec.Right + 3, 0, Width - checkRec.Right - 6, this.Height);
        }


        /// <summary>
        /// 画勾选
        /// </summary>
        /// <param name="g"></param>
        /// <param name="rectangle"></param>
        /// <param name="color"></param>
        private void DrawCheckFlag(Graphics g, Rectangle rectangle, Color color)
        {
            PointF[] pointFs = new PointF[3];

            pointFs[0] = new PointF(rectangle.X + rectangle.Width / 4.5f, rectangle.Y + rectangle.Height / 2.5f);
            pointFs[1] = new PointF(rectangle.X + rectangle.Width / 2.5F, rectangle.Bottom - rectangle.Height / 3.0f);
            pointFs[2] = new PointF(rectangle.Right - rectangle.Width / 4.0f, rectangle.Y + rectangle.Height / 4.5f);

            Pen pen = new Pen(color, 2.0f);
            g.DrawLines(pen, pointFs);

        }
    }
}