web前端js绘制统计图表,访问数据库
现在有很多js库可以方便地在web客户端绘制出漂亮的统计图表，显示效果和开发易用性并不亚于在JSP Server端使用诸如JFreeChart组件生成图片流传递到客户端。
一般要求浏览器支持html5的canvas功能，为兼容不支持的浏览器，js库另外提供了canvas脚本库。
本例记录了采用免费开源基于jquery的js绘图库—— jqplot、MS ActiveX框架、MS Acess 开发学习实例.
部分源码：
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Statistics</title>
<link type="text/css" rel="stylesheet" href="../css/pagestyle.css"/>
<script type="text/javascript" src="../js/jquery.min.js"></script>
<script language="javascript" type="text/javascript" src="../js/excanvas.js"></script>
<script language="javascript" type="text/javascript" src="../js/jquery.jqplot.min.js"></script>
<script type="text/javascript" src="../js/jqplot.dateAxisRenderer.min.js"></script>
<link rel="stylesheet" type="text/css" hrf="../css/jquery.jqplot.min.css" />
<script type="text/javascript">
var drawline = function(obj,areaid,tt){
//var line1=[['2008-08-12 4:00PM',4], ['2008-09-12 4:00PM',6.5], ['2008-10-12 4:00PM',5.7], ['2008-11-12 4:00PM',9], ['2008-12-12 4:00PM',8.2]];
var line1 = obj;
var plot1 = $.jqplot(areaid, [line1], {
title:tt,
axes:{
xaxis:{
renderer:$.jqplot.DateAxisRenderer,
tickOptions:{formatString:'%Y/%#m/%#d'}
}
},
series:[{lineWidth:4, markerOptions:{style:'square'}}]
});
}
var getData = function(sql,a1,line){
//查询数据
// var a = new Array(3);
// a[0] = new Array(1,2,3);
// a[1] = new Array(3,4,5);
var filefolder = location.href.substring(0, location.href.indexOf("statistics.html"));
var dbpath = filefolder.substring(8) + "../db/oilcar.mdb" ; //去掉 "file:///" ,路径有效
var con = new ActiveXObject("ADODB.Connection"),
fso = new ActiveXObject("Scripting.FileSystemObject"), //①
connstr = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + fso.GetFile(dbpath); // ① 这种写法有效
con.Open(connstr); //①
var rs = new ActiveXObject("ADODB.Recordset");
rs.open(sql,con);
while(!rs.eof){
var theday = rs.Fields.item("date_jiayou").value;
var carnum =rs.Fields.item("carnumber").value; //号牌
var miles = rs.Fields.item("totalmileage").value; //总里程，整数
var oilleft = rs.Fields.item("oilboxpercent").value;
var price = rs.Fields.item("per_price").value; //价格，实数
var oiltype = rs.Fields.item("oiltype").value; //类型
var quantity = rs.Fields.item("quantity").value; //量，实数
var fee = rs.Fields.item("pay").value; //总费用，实数
var seller = rs.Fields.item("seller").value; //商家
var place = rs.Fields.item("location").value; //地点
var remark = rs.Fields.item("remark").value; //备注
palce = (place=="")?"":place;
remark = (remark=="")?"":remark;
var d = new Date(Date.parse(theday));
var y,m,day;
y = d.getFullYear();
m = d.getMonth()+1 ;
day = d.getDate();
theday = y +"/" + m + "/" + day;
oilleft = Number(oilleft).toFixed(4); //剩余百分比，小数
a1[line] = new Array();
a1[line][0] = Date.parse(theday);
a1[line][1] = new Number(oilleft);//这里必须new对象，否则还会传递原对象，导致本函数被调用处(111行)提示“对象不再有效”
a1[line][2] = new Number(miles);//这里必须new对象，否则还会传递原对象，导致本函数被调用处(111行)提示“对象不再有效”
a1[line][3] = new Number(price);//这里必须new对象，否则还会传递原对象，导致本函数被调用处(111行)提示“对象不再有效”
a1[line][4] = new Number(quantity);//这里必须new对象，否则还会传递原对象，导致本函数被调用处(111行)提示“对象不再有效”
//a1[line] = new Array(theday,oilleft,miles,price,quantity);
//alert(a1[line]);
line++;
rs.moveNext;
}
rs.close();
rs = null;
con.Close();
con = null;
// alert(a1[0]);
return a1;
}
var getPrices = function(sql,a2,line){
var filefolder = location.href.substring(0, location.href.indexOf("statistics.html"));
var dbpath = filefolder.substring(8) + "../db/oilcar.mdb" ; //去掉 "file:///" ,路径有效
var con = new ActiveXObject("ADODB.Connection"),
fso = new ActiveXObject("Scripting.FileSystemObject"), //①
connstr = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + fso.GetFile(dbpath); // ① 这种写法有效
con.Open(connstr); //①
var rs = new ActiveXObject("ADODB.Recordset");
rs.open(sql,con);
while(!rs.eof){
var theday = rs.Fields("date_jiayou");
var carnum =rs.Fields("carnumber"); //号牌
var miles = rs.Fields("totalmileage"); //总里程，整数
var oilleft = rs.Fields("oilboxpercent");
var price = rs.Fields("per_price"); //价格，实数
var oiltype = rs.Fields("oiltype"); //类型
var quantity = rs.Fields("quantity"); //量，实数
var fee = rs.Fields("pay"); //总费用，实数
var seller = rs.Fields("seller"); //商家
var place = rs.Fields("location"); //地点
var remark = rs.Fields("remark"); //备注
palce = (place=="")?"":place;
remark = (remark=="")?"":remark;
var d = new Date(Date.parse(theday));
var y,m,day;
y = d.getFullYear();
m = d.getMonth()+1 ;
day = d.getDate();
theday = y +"/" + m + "/" + day;
oilleft = Number(oilleft).toFixed(4); //剩余百分比，小数
a2[line] = new Array();
a2[line][0] = new Date(Date.parse(theday));
a2[line][1] = new Number(price);//这里必须new对象，否则还会传递原对象，导致本函数被调用处(111行)提示“对象不再有效”
line++;
rs.moveNext;
}
rs.close();
rs = null;
con.Close();
con = null;
return a2;
}
$(function(){
$("#st").click(function(){
var a1 = new Array();
var line = 0;
$("#dv_1").html("");
var y = Number($("#t1").val());//需要验证....
var d1 = y+"/"+ 1 + "/"+1;
var d2 = (y+1)+"/"+ 1+ "/"+1;
//alert(d2);
var sql = "select * from oilcarlog where date_jiayou>=#"+ d1+"# and date_jiayou<#"+ d2 +"# order by date_jiayou asc ";
//var arr = getData(sql);
var obj = getData(sql,a1,line);//二维数组 : /日期 /油剩余百分比 /里程 /单价 /加油量
//alert(obj[1]);
var bar_x = new Array(), bar_y = new Array() ;//x:日期 y:油耗
for(i=1;i<obj.length;i++){
var cur_oilleft = obj[i][1];//当前行剩油百分比
var oil_spent = 0 ;//油耗，指到上一次或前面某次加油时所加的油之和
var cur_miles = obj[i][2] ; //当前行里程
var miles_travel = 0 ;
var haspoint_calc = false;
for(j=i-1;j>=0;j--){
//剩油百分比小于等于1/16时，近似算作这次与计算行（待计算日）剩油百分比相同，以便累计待计算的总油耗：前几次到当前日期(当前日期不含)所加油量之和
var percent = cur_oilleft - obj[j][1];
oil_spent += obj[j][4];
miles_travel = cur_miles - obj[j][2];
if( percent <= 0.0625 ){
//找到可计算日期
haspoint_calc = true;
break;
}
}
if(haspoint_calc){
var d = new Date(obj[i][0]);
// var year = d.getFullYear() , month = d.getMonth + 1;
var date_calc = new String(d.getFullYear() + "/" + String(new Number(d.getMonth()) + 1) + "/" + new String(d.getDate()));
var oil = new Number(100*oil_spent/miles_travel);//百公里油耗 升/百公里
bar_x.push( date_calc );
bar_y.push( oil.toFixed(2) );
}
}
var obj = new Array();
for(k=0;k<bar_x.length;k++){
obj[k] = new Array(String(bar_x[k]),Number(bar_y[k]));
}
drawline(obj,'dv_1','汽车油耗统计(升/百公里)');
});
$("#oil").click(function(){
var a2 = new Array();
var line = 0;
$("#dv_1").html("");
var y = Number($("#t1").val());//需要验证....
var d1 = y+"/"+ 1 + "/"+1;
var d2 = (y+1)+"/"+ 1+ "/"+1;
var sql = "select * from oilcarlog where date_jiayou>=#"+ d1+"# and date_jiayou<#"+ d2 +"# order by date_jiayou asc ";
var obj = getPrices(sql,a2,line);//二维数组 : /日期 /单价
drawline(obj,'dv_1','汽油单价浮动');
});
});
</script>
</head>
<body>
<div style="height: 99%;">
<div style="height: 10%;">
<label style="font-size: 13px; font-style: normal; font-weight: bold;">统计年份:</label>
<input type="text" id="t1" name="theday" value="2015" /><span style="font-size: 10px">(如：2015)</span>
<input type="button" value="统计" class="btn_statistics" id="st" />|<input type="button" value="油价浮动" class="btn_statistics" id="oil" />
</div>
<div style="height: 90%;">
<fieldset style="font-size: 14px; color:blue; width: 90%; height:90% ">
<legend>查询图表</legend>
<div id="dv_1" style="width:600px; height:350px; margin-top:20px; margin-left:20px;">
</div>
</fieldset>
</div>
</div>
</body>
</html>
链接：http://www.jqplot.com/