c#画图之柱形图
2021-05-18 23:28
标签:lin ack res 创建 http 保存 ring white 输出 效果图 c#画图之柱形图 标签:lin ack res 创建 http 保存 ring white 输出 原文地址:https://www.cnblogs.com/zhoushangwu/p/11725445.htmlpublic JsonResult DrawBarChart()
{
#region 允许配置项
//定义宽高
int height = 500, width = 700;
//边缘位置留白
int margin_top = 20;
int margin_right = 40;
int margin_bottom = 60;
int margin_left = 60;
//辅助线距离顶部的距离
int xsubline = 20;
//文字大小,单位:px
int fontsize = 12;
#endregion
#region 数据
//最大数量/总数量
int maxCount = 0;
string[] bottomData = new string[] { "第一个", "第二个", "第三个", "第四个", "第五个" };
int[] barData = new int[] { 24, 33, 11, 55, 22 };
maxCount = barData.Max();
maxCount = maxCount == 0 ? 5 : maxCount;
#endregion
//单位转换对象
Spire.Pdf.Graphics.PdfUnitConvertor unitCvtr = new Spire.Pdf.Graphics.PdfUnitConvertor();
//生成图像对象
Bitmap image = new Bitmap(width + margin_left + margin_right, height + margin_top + margin_bottom);
//创建画布
Graphics g = Graphics.FromImage(image);
//黑色画笔--主轴颜色
Brush blackBrush = new SolidBrush(Color.FromArgb(255, 102, 102, 102));
Pen blackPen = new Pen(blackBrush, 1);
//灰色画笔--辅助线条颜色
Brush grayBrush = new SolidBrush(Color.FromArgb(255, 224, 224, 224));
Pen grayPen = new Pen(grayBrush, 1);
//填充区域内容
g.FillRectangle(Brushes.WhiteSmoke, 0, 0, width + margin_left + margin_right, height + margin_top + margin_bottom);
//y轴
g.DrawLine(blackPen, margin_left, margin_top, margin_left, (height + margin_top));
//x轴
g.DrawLine(blackPen, margin_left, (height + margin_top), (width + margin_left), (height + margin_top));
Font font = new Font("宋体", unitCvtr.ConvertUnits(fontsize, Spire.Pdf.Graphics.PdfGraphicsUnit.Pixel, Spire.Pdf.Graphics.PdfGraphicsUnit.Point));
//x轴--辅助线
//画5条辅助线,不管数字大小
int avgCount = Convert.ToInt32(Math.Ceiling(maxCount / 5.0));
int lineHeight = (height - xsubline) / 5;
//画辅助线与文字
for (int i = 0; i 5; i++)
{
//辅助线
if (i > 0)
{
g.DrawLine(grayPen, margin_left, (height + margin_top - lineHeight * i), (width + margin_left), (height + margin_top - lineHeight * i));
}
//指向文字的线
g.DrawLine(blackPen, (margin_left - 5), (height + margin_top - lineHeight * i), margin_left, (height + margin_top - lineHeight * i));
//文字
int text = avgCount * i;
if (i == 5)
{
if (maxCount - text > 0)
{
text = text + (maxCount - text);
}
}
RectangleF rec = new RectangleF(10, (height + margin_top - lineHeight * i - fontsize / 2), margin_left - 20, 20);
//public void DrawString(string s, Font font, Brush brush, RectangleF layoutRectangle);
//g.DrawString(text.ToString(), font, blackBrush, 10, (height + margin_top - lineHeight * i));
StringFormat format = new StringFormat(StringFormatFlags.DirectionRightToLeft);
g.DrawString(text.ToString(), font, blackBrush, rec, format);
}
//蓝色画笔--柱子的颜色
Brush blueBrush = new SolidBrush(Color.FromArgb(255, 63, 167, 220));
Pen bluePen = new Pen(blueBrush, 1);
int singleWidth = width / barData.Length;
for (int i = 0; i )
{
StringFormat format = new StringFormat();
format.Alignment = StringAlignment.Center; //居中
//计算柱子
int pillarHeight = Convert.ToInt32(barData[i] / Convert.ToDouble(maxCount) * (height - xsubline));
//这里是画柱子的代码
Rectangle rectangle = new Rectangle(margin_left + (i * singleWidth + singleWidth / 4), height + margin_top - pillarHeight, singleWidth / 2, pillarHeight);
g.FillRectangle(blueBrush, rectangle);
//柱子上的文字
RectangleF recText = new RectangleF(margin_left + (i * singleWidth), (height + margin_top - pillarHeight - 20), singleWidth, 20);
g.DrawString(barData[i].ToString(), font, blackBrush, recText, format);
//x轴下的文字
//指向线
g.DrawLine(blackPen, margin_left + (i * singleWidth + singleWidth / 2), (height + margin_top), margin_left + (i * singleWidth + singleWidth / 2), (height + margin_top + 5));
//文字
RectangleF rec = new RectangleF(margin_left + (i * singleWidth), (height + margin_top + 15), singleWidth, (margin_bottom - 20));
g.DrawString(bottomData[i].ToString(), font, blackBrush, rec, format);
}
//将图片保存到指定的流中,适用于直接以流的方式输出图片
//System.IO.MemoryStream ms = new System.IO.MemoryStream();
//image.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
//Response.ClearContent();
//Response.ContentType = "image/Jpeg";
//Response.BinaryWrite(ms.ToArray());
string relativePath = @"\draw-image\" + DateTime.Now.ToString("yyyyMMddHHmmssfff") + ".jpg";
string path = Server.MapPath(relativePath);
image.Save(path, System.Drawing.Imaging.ImageFormat.Jpeg);
//return relativePath;
return Json(relativePath, JsonRequestBehavior.AllowGet);
}