using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
using System.Drawing.Imaging;
namespace 实现简单曲线图
{
/// <summary>
/// WebForm1 的摘要说明。
/// </summary>
public class LineChart : System.Web.UI.Page
{
public Bitmap b ;
public string Title = "在ASP.NET中实现数据图表" ;
public ArrayList chartValues = new ArrayList ( ) ;
public float Xorigin = 0 , Yorigin = 0 ;
public float ScaleX , ScaleY ;
public float Xdivs = 2 , Ydivs = 2 ;
private int Width , Height ;
private Graphics g ;
private Page p ;
struct datapoint
{
public float x;
public float y;
public bool valid;
}
private void Page_Load(object sender, System.EventArgs e)
{
// 在此处放置用户代码以初始化页面
LineChart c= new LineChart ( 640 , 480 , Page ) ;
c.Title = " 在ASP.NET中实现数据图表" ;
c.Xorigin = 0 ; c.ScaleX = 500 ; c . Xdivs = 5 ;
c . Yorigin = 0 ; c . ScaleY = 1000 ; c . Ydivs = 5 ;
c . AddValue ( 0 , 150 ) ;
c . AddValue ( 50 , 50 ) ;
c . AddValue ( 100 , 700 ) ;
c . AddValue ( 200 , 150 ) ;
c . AddValue ( 300 , 450 ) ;
c . AddValue ( 400 , 75 ) ;
c . AddValue ( 450 , 450 ) ;
c . AddValue ( 500 , 250 ) ;
c . Draw ( ) ;
}
#region Web 窗体设计器生成的代码
override protected void OnInit(EventArgs e)
{
//
// CODEGEN: 该调用是 ASP.NET Web 窗体设计器所必需的。
//
InitializeComponent();
base.OnInit(e);
}
/// <summary>
/// 设计器支持所需的方法 - 不要使用代码编辑器修改
/// 此方法的内容。
/// </summary>
private void InitializeComponent()
{
this.Load += new System.EventHandler(this.Page_Load);
}
#endregion
public LineChart( int myWidth , int myHeight , Page myPage )
{
Width = myWidth ; Height = myHeight ;
ScaleX = myWidth ; ScaleY = myHeight ;
b = new Bitmap ( myWidth , myHeight ) ;
g = Graphics . FromImage ( b ) ;
p = myPage ;
}
public void AddValue ( int x , int y )
{
datapoint myPoint ;
myPoint . x = x ;
myPoint . y = y ;
myPoint . valid = true ;
chartValues . Add ( myPoint ) ;
}
public void Draw ( )
{
int i ;
float x , y , x0 , y0 ;
string myLabel ;
Pen blackPen = new Pen ( Color . Blue , 2 ) ;//定义画笔
Brush blackBrush = new SolidBrush ( Color . Black ) ;//定义画刷
Font axesFont = new Font ( "arial" , 10 ) ;//定义字体
//首先要创建图片的大小
p . Response . ContentType = "image/jpeg" ;
g . FillRectangle ( new SolidBrush ( Color . LightGreen ) , 0 , 0 , Width , Height ) ;
int ChartInset = 50 ;
int ChartWidth = Width - ( 2 * ChartInset ) ;
int ChartHeight = Height - ( 2 * ChartInset ) ;
g . DrawRectangle ( new Pen ( Color . Black , 1 ) , ChartInset , ChartInset , ChartWidth , ChartHeight ) ;
//写出图片上面的图片内容文字
g . DrawString ( Title , new Font ( "arial" , 14 ) , blackBrush , Width / 3 , 10 ) ;
//沿X坐标写入X标签
for ( i = 0 ; i <= Xdivs ; i++ )
{
x = ChartInset + ( i * ChartWidth ) / Xdivs ;
y = ChartHeight + ChartInset ;
myLabel = ( Xorigin + ( ScaleX * i / Xdivs ) ) . ToString ( ) ;
g . DrawString ( myLabel , axesFont , blackBrush , x - 4 , y + 10 ) ;
g . DrawLine ( blackPen , x , y + 2 , x , y - 2 ) ;
}
//沿Y坐标写入Y标签
for ( i = 0 ; i <= Ydivs ; i++ )
{
x = ChartInset ;
y = ChartHeight + ChartInset - ( i * ChartHeight / Ydivs ) ;
myLabel = ( Yorigin + ( ScaleY * i / Ydivs ) ) . ToString ( ) ;
g . DrawString ( myLabel , axesFont , blackBrush , 5 , y - 6 ) ;
g . DrawLine ( blackPen , x + 2 , y , x - 2 , y ) ;
}
g . RotateTransform ( 180 ) ;
g . TranslateTransform ( 0 , - Height ) ;
g . TranslateTransform ( - ChartInset , ChartInset ) ;
g . ScaleTransform ( - 1 , 1 ) ;
//画出图表中的数据
datapoint prevPoint = new datapoint ( ) ;
prevPoint.valid = false ;
foreach ( datapoint myPoint in chartValues )
{
if ( prevPoint . valid == true )
{
x0 = ChartWidth * ( prevPoint . x - Xorigin ) / ScaleX ;
y0 = ChartHeight * ( prevPoint . y - Yorigin ) / ScaleY ;
x = ChartWidth * ( myPoint . x - Xorigin ) / ScaleX ;
y = ChartHeight * ( myPoint . y - Yorigin ) / ScaleY ;
g . DrawLine ( blackPen , x0 , y0 , x , y ) ;
g . FillEllipse ( blackBrush , x0 - 2 , y0 - 2 , 4 , 4 ) ;
g . FillEllipse ( blackBrush , x - 2 , y - 2 , 4 , 4 ) ;
}
prevPoint = myPoint ;
}
//最后以图片形式来浏览
b . Save ( p . Response . OutputStream , ImageFormat . Jpeg ) ;
}
~LineChart( )
{
g . Dispose ( ) ;
b . Dispose ( ) ;
}