解析PHP生成图表pChart的示例-php教程

pChart是一个开源的图表生成库，主要涉及3个Class：pChart.class, pData.class, pCache.class，可生成20多种简单或复杂的图表，支持PNG，JPG，GIF通用图片格式。数据源可以来自于Database，CSV，当然也可以手写。使用该程序PHP需要开启GD服务，先来看看pChart的工作流程：

主要分为三步：

* 读取用于生成图表数据（数据库、文件）

* 设计图表样式（圆角、底色等）

* 制作标签、题目、图例并生成图表

下面看一个简单的柱状图表：

代码如下：

<?php
// Standard inclusions
include("pChart/pData.class");
include("pChart/pChart.class");
// Dataset definition
$DataSet = new pData;
//图表数据
$DataSet->AddPoint(array(1,4,-3,2,-3,3,2,1,0,7,4),"Serie1");
$DataSet->AddPoint(array(3,3,-4,1,-2,2,1,0,-1,6,3),"Serie2");
$DataSet->AddPoint(array(4,1,2,-1,-4,-2,3,2,1,2,2),"Serie3");
$DataSet->AddAllSeries();
$DataSet->SetAbsciseLabelSerie();
//数据图例
$DataSet->SetSerieName("Microsoft","Serie1");
$DataSet->SetSerieName("IBM","Serie2");
$DataSet->SetSerieName("Google","Serie3");
// Initialise the graph
$Test = new pChart(700,230);
//设置图表尺寸、样式
$Test->setFontProperties("Fonts/tahoma.ttf",8);
$Test->setGraphArea(50,30,680,200);
$Test->drawFilledRoundedRectangle(7,7,693,223,5,240,240,240);
$Test->drawRoundedRectangle(5,5,695,225,5,230,230,230);
$Test->drawGraphArea(255,255,255,TRUE);
$Test->drawScale($DataSet->GetData(),$DataSet->GetDataDescription(),SCALE_NORMAL,150,150,150,TRUE,0,2,TRUE);
$Test->drawGrid(4,TRUE,230,230,230,50);
// Draw the 0 line
$Test->setFontProperties("Fonts/MankSans.ttf",6);
$Test->drawTreshold(0,143,55,72,TRUE,TRUE);
// Draw the bar graph
//柱状图要使用drawBarGraph()
$Test->drawBarGraph($DataSet->GetData(),$DataSet->GetDataDescription(),TRUE,80);
// Finish the graph
//制作图例、标题、字体等属性
$Test->setFontProperties("Fonts/MankSans.ttf",10);
$Test->drawLegend(596,150,$DataSet->GetDataDescription(),255,255,255);
$Test->setFontProperties("Fonts/MankSans.ttf",10);
$Test->drawTitle(50,22,"Example",50,50,50,585);
//生成图表
$imageFile = "example12.png";
$Test->Render($imageFile);
echo '<img src="'.$imageFile.'">';
?>

这个是雷达效果的：

代码：

<?php
// Standard inclusions
include("pChart/pData.class");
include("pChart/pChart.class");
// Dataset definition
$DataSet = new pData;
$DataSet->AddPoint(array("Memory","Disk","Network","Slots","CPU"),"Label");
$DataSet->AddPoint(array(6,4,7,4,5),"Serie1");
$DataSet->AddPoint(array(2,3,5,2,4),"Serie2");
$DataSet->AddSerie("Serie1");
$DataSet->AddSerie("Serie2");
$DataSet->SetAbsciseLabelSerie("Label");
$DataSet->SetSerieName("Reference","Serie1");
$DataSet->SetSerieName("Tested computer","Serie2");
// Initialise the graph
$Test = new pChart(400,400);
$Test->setFontProperties("Fonts/tahoma.ttf",8);
$Test->drawFilledRoundedRectangle(7,7,393,393,5,240,240,240);
$Test->drawRoundedRectangle(5,5,395,395,5,230,230,230);
$Test->setGraphArea(30,30,370,370);
$Test->drawFilledRoundedRectangle(30,30,370,370,5,255,255,255);
$Test->drawRoundedRectangle(30,30,370,370,5,220,220,220);
// Draw the radar graph
//要使用drawRadarAxis()生成雷达效果
$Test->drawRadarAxis($DataSet->GetData(),$DataSet->GetDataDescription(),TRUE,20,120,120,120,230,230,230);
$Test->drawFilledRadar($DataSet->GetData(),$DataSet->GetDataDescription(),50,20);
// Finish the graph
$Test->drawLegend(15,15,$DataSet->GetDataDescription(),255,255,255);
$Test->setFontProperties("Fonts/tahoma.ttf",10);
$Test->drawTitle(0,22,"Example",50,50,50,400);
$imageFile = "example8.png";
$Test->Render($imageFile);
echo '<img src="'.$imageFile.'">';
?>