得到数据库中的数据，并在Highcharts控件中显示

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//得到数据库中的数据，并在Highcharts控件中显示
[WebMethod]
public static string getDataTableByAjax()
{
//连接字符串
string sqlConnStr = "DataSource=NUAA-PC\\SQLEXPRESS;Initial Catalog=TempData;IntegratedSecurity=True";
//数据集和数据适配器
DataSetds = new DataSet("GetValue");
SqlDataAdapterda = new SqlDataAdapter();
using (SqlConnection sqlConn= new SqlConnection(sqlConnStr))
{
try
{
sqlConn.Open();
//存储过程,”Get_Value”为存储过程名
SqlCommandsqlComm = newSqlCommand("Get_Value",sqlConn);
sqlComm.CommandType = CommandType.StoredProcedure;
//添加查询参数和值
sqlComm.Parameters.Add("@starttime", SqlDbType.DateTime).Value= currenttime;
sqlComm.Parameters.Add("@endtime", SqlDbType.DateTime).Value= currenttime.AddMinutes(2);
//执行存储过程
sqlComm.ExecuteNonQuery();
da.SelectCommand = sqlComm;
da.Fill(ds);
//创建存储返回值的表
DataTabledt = new DataTable();
//为表增加两个列，列名分别为x和y
dt.Columns.Add("x", typeof(string));
dt.Columns.Add("y", typeof(float));
//将存储过程中的表复制到返回表中
foreach(DataRow drin ds.Tables[0].Rows)
{
DataRownewdr = dt.NewRow();
newdr["x"] = dr[0].ToString();
newdr["y"] = dr[1];
dt.Rows.Add(newdr);
}
//更新currenttime，下次再访问该函数时，便得到不同的值，实现“实时”的要求
currenttime= currenttime.AddMinutes(2);
stringresult = Dtb2Json(dt).ToString();
returnresult.ToString();
}
catch
{
throw new Exception("调用Ajax Error");
}
finally
{
sqlConn.Dispose();
}
}
}

#region DataTablel Json
public static string Dtb2Json(DataTabledtb)
{
JavaScriptSerializerjss = new JavaScriptSerializer();
ArrayListdic = new ArrayList();
foreach (DataRow row in dtb.Rows)
{
Dictionary<string, object> drow = new Dictionary<string,object>();
foreach(DataColumn colin dtb.Columns)
{
drow.Add(col.ColumnName, row[col.ColumnName]);
}
dic.Add(drow);
}
return jss.Serialize(dic);
}
#endregion
⑤ 在Default.aspx中适当地方加入以下代码：

[javascript] view plaincopy在CODE上查看代码片派生到我的代码片
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
<title>故障监测主页</title>
<!—注意文件名应该和你下载的文件名保持一致 -->
<script type="text/javascript"src="JS/jquery.min.js"></script>
<script type="text/javascript"src="JS/highcharts.js"></script>
<script type="text/javascript">
//<![CDATA[
$(function(){
Highcharts.setOptions({
global: {
useUTC: false
}
});
//声明报表对象
var chart = new Highcharts.Chart({
chart:{
//将报表对象渲染到层上
renderTo:'container' ,
defaultSeriesType:'spline'
}, //chart end
title:{
text:'实时PCA曲线'
},
yAxis:{
title:{
text:'PCA值'
}
},
//设定报表对象的初始数据
series:[{
data:[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
}]
}); //Highcharts.Chart end

//获取后台数据
functiongetForm(){
$.ajax({
type:"Post",
//后台获取数据的函数，注意当对该页面重命名时，
//必须手动更改该选项
url: "Default.aspx/getDataTableByAjax",
contentType:"application/json; charset=utf-8",
dataType:"json",
//成功获取数据
success:function (data){
data= jQuery.parseJSON(data.d); //JSON再次转换为Table 形式；
varseries= chart.series[0];
series.addPoint([data[0]["x"],data[0]["y"]],false,true);
chart.redraw();
},
//显示错误
error:function (err){
alert(err + "调用后台程序出现错误，请尝试刷新！");
}
});
}

$(document).ready(function() {
//每隔3秒自动调用方法，实现图表的实时更新
window.setInterval(getForm,2000);
});
});
//]]>
</script>
</head>
<body>
<div id="container" style="width: 800px; height: 600px; margin: 0 auto"></div>
</body>
</html>

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