//绘制柱形图
Total方法是计算一年内的总流量，先忽略根据自己情况编写；
int w = 600;
int h = 400;
Bitmap b = new Bitmap(w,h);
Graphics g = Graphics.FromImage(b);
g.Clear(Color.White);
LinearGradientBrush brush = new LinearGradientBrush(new Rectangle(0, 0, b.Width, b.Height), Color.Blue, Color.BlueViolet, 1.2f, true);
Font font = new Font("Arial",7, FontStyle.Regular);
Font font1 = new Font("宋体", 20, FontStyle.Bold);
g.FillRectangle(Brushes.WhiteSmoke, 0, 0, w, h);
g.DrawString("2022年各月份流量统计", font1, brush, new PointF(130, 30));
g.DrawRectangle(new Pen(Color.Blue), 0, 0, w - 1, h - 1);
Pen p = new Pen(brush, 1);
//绘制竖线
int x = 100;
for (int i = 0; i < 11; i++)
{
g.DrawLine(p, x, 80, x, 340);
x = x + 40;
}
g.DrawLine(new Pen(Color.Blue, 2), x - 480, 80, x - 480, 340);
//绘制横线
int y1 = 106;
for (int y = 0; y < 9; y++)
{
g.DrawLine(p, 60, y1, 540, y1);
y1 = y1 + 26;
}
g.DrawLine(new Pen(Color.Blue, 2), 60, y1, 540, y1);
string[] n = { "一月", "二月", "三月", "四月", "五月", "六月", "七月", "八月", "九月", "十月", "十一月", "十二月"};
x = 62;
for (int i = 0; i < 12; i++)
{
g.DrawString(n[i], font, Brushes.Black, x, 350);
x = x + 40;
}
string[] m1 = {"100%", "90%", "80%", "70%", "60%", "50%", "40%", "30%", "20%", "10%","0%" };
y1 = 85;
for (int i = 0; i < 11; i++)
{
g.DrawString(m1[i], font, Brushes.Black, 25, y1);
y1 = y1 + 26;
}
int[] count = new int[12];
SqlConnection c = new SqlConnection(ConfigurationManager.AppSettings["cons"]);
c.Open();
SqlDataAdapter d;
string cmdStr="";
DataSet ds = new DataSet();
for (int i = 0; i < 12; i++)
{
cmdStr = "select count(*) as count,month(logintime) logintime from tb_10 where year(logintime)=2007 and month(logintime)="+i+1+ " group by month(logintime)";
d = new SqlDataAdapter(cmdStr, c);
d.Fill(ds, i.ToString());
if (ds.Tables[i].Rows.Count == 0)
{
count[i] = 0;
}
else
{
count[i] = Convert.ToInt32(ds.Tables[i].Rows[0][0])*100/Total();
}
}
//绘制方形块
x = 70;
for (int i = 0; i < 12; i++)
{
g.FillRectangle(new SolidBrush(Color.Blue), x, 340 - count[i] * 26 / 10, 20, count[i] * 26 / 10);
x = x + 40;
}
System.IO.MemoryStream m = new System.IO.MemoryStream();
b.Save(m, System.Drawing.Imaging.ImageFormat.Jpeg);
Response.ClearContent();
Response.ContentType = "image/Jpeg";
Response.BinaryWrite(m.ToArray());
图示：
