D3js-对柱状图的增，删，排序

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">

<title>D3 添加删除排序柱状图</title>

<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">

</head>

<body>
<script type="text/javascript" src="js/d3/d3.js"></script>
<script type="text/javascript" src="js/d3/d3.min.js"></script>

<script type="text/javascript">

//定义变量
var width =1000;
var height=600;

var dataset=[];

var svg = d3.select("body").append("svg")
.attr("width".width)
.attr("height",height);

for(var i=0;i<5;i++)
{
dataset[i]=Math.floor(Math.random()*100);
}

console.log(dataset);
//外边框
var padding={top:20,right:20,bottom:20,left:20};
//矩形宽度包含空白
var rectStep=35;
//矩形宽度不包含空白
var rectWidth=30;

//绘制矩形
function draw()
{
//1-----------------------------------
//获取矩形updata部分
var updateRect = svg.selectAll("rect")
.data(dataset);

//获取矩形的enter部分
var enterRect =updateRect.enter();

//获取矩形的exit部分
var exitRect =updateRect.exit();

//获取矩形update方法的处理
updateRect.attr("fill","steelblue")
//矩形坐标
.attr("x",function(d,i)
{
return padding.left+i*rectStep;
})
.attr("y",function(d,i)
{
return height-padding.bottom-d;
})
//矩形的高宽
.attr("width",rectWidth)
.attr("height",function(d,i)
{
return d;
});
//获取矩形 enter方法的处理
enterRect.append("rect")
.attr("fill","steelblue")
//矩形坐标
.attr("x",function(d,i)
{
return padding.left+i*rectStep;
})
.attr("y",function(d,i)
{
return height-padding.bottom-d;
})
//矩形的高宽
.attr("width",rectWidth)
.attr("height",function(d,i)
{
return d;
});

//获取矩形exit方法的处理
exitRect.remove();

//2--------------------------------------

//获取文字update的处理
var updateText = svg.selectAll("text")
.data(dataset);

var enterText = updateText.enter();

var exitText = updateText.exit();

updateText.attr("fill","white")
.attr("font-size","14px")
.attr("text-anchor","middle")
.attr("x",function(d,i)
{
return padding.left+i*rectStep;
})
.attr("y",function(d,i)
{
return height-padding.bottom-d;
})
.attr("dx",rectWidth/2)
.attr("dy","1em")
.text(function(d,i)
{
return d;
});
enterText.append("text")
.attr("fill","white")
.attr("font-size","14px")
.attr("text-anchor","middle")
.attr("x",function(d,i)
{
return padding.left+i*rectStep;
})
.attr("y",function(d,i)
{
return height-padding.bottom-d;
})
.attr("dx",rectWidth/2)
.attr("dy","1em")
.text(function(d,i)
{
return d;
});

exitText.remove();
}

//调用画图函数
draw();

//排序
function sortData()
{
dataset.sort(d3.ascending);
draw();
}

//添加
function addData()
{
dataset.push(Math.floor(Math.random()*100));
draw();
}
//删除
function deleteData()
{
//选中全部条
dataset.shift();
var bars = svg.selectAll("rect")
.data(dataset);

bars.exit()
.remove();
draw();
}
</script>

<br/>
<div>
<button type="button" onclick="sortData()">排序</button>
<button type="button" onclick="addData()">添加</button>
<button type="button" onclick="deleteData()">删除</button>

</div>
</body>

</html>

參考站点：http://www.ourd3js.com/wordpress/?p=841

http://blog.csdn.net/tianxuzhang/article/details/14086627