用c#畫餅圖和條形圖，做數據統計

先上效果圖：

餅圖：

條形圖：

 

通過在網上找資料，自己稍微整理下，注釋配代碼如下：

1、畫餅圖的全部代碼

/// <summary>       

/// 根據四率 得到扇形圖       

/// </summary>       

/// <param name="width"></param>       

/// <param name="heigh"></param>       

/// <param name="r">餅圖半徑</param>       

/// <param name="familyName"></param>       

/// <param name="data"></param>       

/// <returns></returns>       

public Bitmap GetBitmap(int width, int heigh, int r,string familyName, Dictionary<string, double> data)       

{           

　　　　Bitmap bitmap = new Bitmap(width, heigh);           

　　　　Graphics graphics = Graphics.FromImage(bitmap);

            //用白色填充整個圖片，因為默認是黑色           

　　　　graphics.Clear(Color.White);

            //抗鋸齒           

　　　　graphics.SmoothingMode = SmoothingMode.HighQuality;

            //高質量的文字           

　　　　graphics.TextRenderingHint = TextRenderingHint.ClearTypeGridFit;

            //像素均偏移0.5個單位，以消除鋸齒           

　　　　graphics.PixelOffsetMode = PixelOffsetMode.Half;

            //第一個色塊的原點位置           

　　　　PointF basePoint = new PointF(10, 20);

            //色塊的大小           

　　　　SizeF theSize = new SizeF(45, 16);

            //第一個色塊的說明文字的位置           

　　　　PointF textPoint = new PointF(basePoint.X + 50, basePoint.Y);           

　　　　foreach (var item in data)           

　　　　{               

　　　　RectangleF baseRectangle = new RectangleF(basePoint, theSize);               

　　　　//畫代表色塊               

　　　　graphics.FillRectangle(new SolidBrush(getColor(item.Key.ToString())), baseRectangle);

          graphics.DrawString(item.Key.ToString(), new Font(familyName, 11), Brushes.Black, textPoint);

          basePoint.Y += 30;               

　　　　textPoint.Y += 30;           

　　　}

 

            //扇形區所在邊框的原點位置           

　　　　Point circlePoint = new Point(Convert.ToInt32( textPoint.X+90),35);

            //總比 初始值           

　　　　float totalRate = 0;           

　　　　//起始角度 Y周正方向           

　　　　float startAngle = 30;           

　　　　//當前比 初始值           

　　　　float currentRate = 0;

            //圓所在邊框的大小           

　　　　Size cicleSize=new Size(r*2,r*2);

            //圓所在邊框的位置           

　　　　Rectangle circleRectangle=new Rectangle(circlePoint,cicleSize);

            foreach (var item in data) totalRate += float.Parse(item.Value.ToString());           

foreach (var item in data)           

{               

　　　　　　currentRate = float.Parse(item.Value.ToString()) / totalRate * 360;

                graphics.DrawPie(Pens.White, circleRectangle, startAngle, currentRate);               

　　　　　　graphics.FillPie(new SolidBrush(getColor(item.Key.ToString())), circleRectangle, startAngle, currentRate);

                //至此 扇形圖已經畫完，下面是在扇形圖上寫上說明文字

                //當前圓的圓心 相對圖片邊框原點的坐標               

　　　　　　PointF cPoint = new PointF(circlePoint.X+r, circlePoint.Y+r);

                //當前圓弧上的點               

　　　　　　//cos(弧度)=X軸坐標/r               

　　　　　　//弧度=角度*π/180               

　　　　　　double relativeCurrentX = r * Math.Cos((360 - startAngle - currentRate / 2) * Math.PI / 180);               

　　　　　　double relativecurrentY = r * Math.Sin((360 - startAngle - currentRate / 2) * Math.PI / 180);

                double currentX = relativeCurrentX+cPoint.X;               

　　　　double currentY = cPoint.Y - relativecurrentY;

                //內圓上弧上的 浮點型坐標               

　　　　PointF currentPoint=new PointF(float.Parse(currentX.ToString()),float.Parse(currentY.ToString()));               

　　　　//外圓弧上的點          

　　      double largerR = r + 25;

                double relativeLargerX = largerR * Math.Cos((360 - startAngle - currentRate / 2) * Math.PI / 180);               

　　　　double relativeLargerY = largerR * Math.Sin((360 - startAngle - currentRate / 2) * Math.PI / 180);

                double largerX = relativeLargerX + cPoint.X;               

　　　　double largerY = cPoint.Y - relativeLargerY;

                //外圓上弧上的 浮點型坐標                

　　　　PointF largerPoint=new PointF(float.Parse(largerX.ToString()),float.Parse(largerY.ToString()));

                //將兩個點連起來                

　　　　　　//graphics.DrawLine(Pens.Black, currentPoint, largerPoint);

                //外圓上 說明文字的位置                

　　　　PointF circleTextPoint = new PointF(float.Parse( largerX.ToString()),float.Parse( largerY.ToString()));                              

　　　　//在外圓上的點的附近合適的位置 寫上說明                

　　if (largerX >= 0 && largerY >= 0)//第1象限  實際第二象限                

{                    

//circleTextPoint.Y -= 15;                    

circleTextPoint.X -= 35;               

  }

                 if (largerX <= 0 && largerY >= 0)//第2象限  實際第三象限                

{                

     //circleTextPoint.Y -= 15;                    

//circleTextPoint.X -= 65;                

}             

    if (largerX <= 0 && largerY <= 0)//第3象限  實際第四象限                

{                 

    //circleTextPoint.X -= 45;               

      circleTextPoint.Y += 30;              

   }               

  if (largerX >= 0 && largerY <= 0)//第4象限  實際第一象限                

{                    

circleTextPoint.X -= 15;                    

//circleTextPoint.Y += 5;                

}

                //象限差異解釋：在數學中 二維坐標軸中 右上方 全為正，在計算機處理圖像時，右下方全為正。相當於順時針移了一個象限序號                              

　　　　graphics.DrawString(item.Key.ToString() + " " + (currentRate/360).ToString("p2"), new Font(familyName, 11), Brushes.Black, circleTextPoint);                       

           startAngle += currentRate;           

}

            return bitmap;      

}

 

2、獲得配色的代碼：

        Color getColor(string scoreLevel)         {           

Color c=Color.White;          

  if (scoreLevel.Contains("優秀"))           

     c = Color.FromArgb(57,134,155);         

   if (scoreLevel.Contains("良好"))               

c = Color.FromArgb(70,161,185);           

if (scoreLevel.Contains("一般"))               

c = Color.FromArgb(124,187,207);           

if (scoreLevel.Contains("不及格"))               

c = Color.FromArgb(181,212,224);

            return c;       

}

3、畫條形圖的代碼

   /// <summary>     

   /// 獲得柱狀圖      

  /// </summary>      

  /// <param name="width"></param>     

   /// <param name="heigh"></param>      

  /// <param name="familyName"></param>      

  /// <param name="data"></param>       

/// <param name="PaperScore"></param>      

  /// <returns></returns>       

public Bitmap GetBargraph(int width, int heigh, string familyName, Dictionary<string, double> data, int PaperScore)      

  {             if (data != null)         

   {

                Bitmap bitmap = new Bitmap(width, heigh);          

      Graphics graphics = Graphics.FromImage(bitmap);             

   //用白色填充整個圖片，因為默認是黑色               

graphics.Clear(Color.White);     

           //抗鋸齒            

    graphics.SmoothingMode = SmoothingMode.HighQuality;        

        //高質量的文字             

   graphics.TextRenderingHint = TextRenderingHint.ClearTypeGridFit;           

     //像素均偏移0.5個單位，以消除鋸齒            

    graphics.PixelOffsetMode = PixelOffsetMode.Half;              

  double maxCount = 0;            

    //以最多人數為基准            

    foreach (var item in data) if (Convert.ToDouble(item.Value.ToString()) > maxCount)                 

       maxCount = Convert.ToDouble(item.Value.ToString());

                //在距離底部25像素的地方 畫上分數線 並標上四個分數         

       //該分數線的寬度是圖片寬度的85%             

   //分數線原點位置        

        PointF scoreLineStartPoint = new PointF(width * 0.15f / 2f, heigh - 25f);        

        //分數線終點位置               

PointF scoreLineEndPoint = new PointF(scoreLineStartPoint.X + width * 0.85f, scoreLineStartPoint.Y);         

       graphics.DrawLine(Pens.Black, scoreLineStartPoint, scoreLineEndPoint);           

     //定義：最多人數的那項占圖片高度的85%             

   //每項*高度的85%/maxCount=該項的高度

                float currentX = width * 0.85f * (1f / 9)//直線上的1/9處為起點            

        + width * 0.15f / 2// 圖片的兩邊 空 15%  ，每邊空15%的一半                     ;        

        float perWidth = width * 0.85f * (1f / 9);              

  foreach (var item in data)              

  {

                    //當前等級的原點描述：Height-25-(人數*0.9/maxcount)           

         float currentHeight = (float)item.Value * 0.85f * heigh / (float)maxCount;

                    //顏色 全部用淡藍色                 

   graphics.FillRectangle(new SolidBrush(Color.FromArgb(70, 161, 187)), currentX, heigh - 25 - currentHeight - 1, perWidth, currentHeight);

                    //畫當前區間的左邊的線                 

   graphics.DrawLine(Pens.Black, currentX, scoreLineStartPoint.Y, currentX, scoreLineStartPoint.Y + 3);

                    //在上面5像素處寫上人數

                    graphics.DrawString(item.Value.ToString() + "（人）", new Font(familyName, 11), Brushes.Black, currentX - 4, heigh - 25 - currentHeight - 1 - 18);

                    graphics.DrawString(item.Key.ToString(), new Font(familyName, 11), Brushes.Black, currentX, scoreLineStartPoint.Y + 3);

                    currentX += perWidth;//向右移一個柱形寬度單位              

      //畫當前區間的右邊的線                

    graphics.DrawLine(Pens.Black, currentX, scoreLineStartPoint.Y, currentX, scoreLineStartPoint.Y + 3);     

               currentX += perWidth;//向右移一個柱形寬度單位                 }

                graphics.DrawString("（等級）", new Font(familyName, 11), Brushes.Black, currentX - perWidth + 3f, scoreLineStartPoint.Y + 3);   

             return bitmap;             }             else return null;         }

4、調用柱狀圖的一般處理程序（餅圖類似）

            string datas = context.Request.QueryString["data"];

            ScoreStatistics s = new ScoreStatistics();           

data = s.TransferToObject<Dictionary<string, double>>(datas);

      

            MemoryStream mem = new MemoryStream();           

Bitmap chart = scoreStaticsBLL.GetBargraph(450, 280, "宋體", data, 120);           

chart.Save(mem, ImageFormat.Jpeg);           

context.Response.ContentType = "image/jpeg";

            context.Response.BinaryWrite(mem.ToArray());

調用圖片的頁面代碼就是一個 圖片控件,src的地址為上面的一般處理程序的相對網站地址