MSChart实例

MSChart是VS中自带的图表控件，功能比较强大，效果也比较丰富。下面只提供一个例子，以供新接触的朋友参考。

先看下效果图：

看完效果图上代码啦。

使用这个控件需要先在页面注册一下。

<%@ Register Assembly="System.Web.DataVisualization, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"
    Namespace="System.Web.UI.DataVisualization.Charting" TagPrefix="asp" %>

如果你是在VS工具箱中直接拖动的，上述注册控件的代码是可以自动生成的。

    <div>
        <asp:DropDownList ID="ddlSelectType" runat="server" AutoPostBack="true">
            <asp:ListItem Text="柱状图" Value="Column" />
            <asp:ListItem Text="饼图" Value="Pie" />
            <asp:ListItem Text="折线图" Value="Line" />
        </asp:DropDownList>
        <div>
            <asp:Chart ID="Chart1" runat="server" BorderlineDashStyle="Solid" BorderlineColor="Gray"
                Width="768px" BackGradientStyle="DiagonalLeft" BackSecondaryColor="AliceBlue"
                BackColor="WhiteSmoke">
                <Legends>
                    <asp:Legend Name="Lgd" BackColor="Transparent" Docking="Top" />
                </Legends>
                <Series>
                    <asp:Series Name="Series1" IsValueShownAsLabel="true" CustomProperties="DrawingStyle=Cylinder, MinPixelPointWidth=20, MaxPixelPointWidth=35, PointWidth=0.3"
                        IsXValueIndexed="False" ShadowOffset="1" Legend="Lgd" ChartArea="ChartArea1" />
                </Series>
                <ChartAreas>
                    <asp:ChartArea Name="ChartArea1" BackColor="White" BackSecondaryColor="Azure" BackGradientStyle="DiagonalLeft"
                        ShadowOffset="2">
                        <AxisY>
                            <MajorGrid LineColor="LightSlateGray" LineDashStyle="Dash" />
                        </AxisY>
                        <AxisX>
                            <MajorGrid Enabled="False" />
                            <LabelStyle Font="Microsoft Sans Serif, 8pt" />
                        </AxisX>
                    </asp:ChartArea>
                </ChartAreas>
            </asp:Chart>
        </div>
    </div>

上面在控件内部设置了很多属性，用于控制图表显示的效果。

        protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                ChartBind(SeriesChartType.Line);
            }
            ddlSelectType.SelectedIndexChanged += new EventHandler(ddlSelectType_SelectedIndexChanged);
        }

        /// <summary>
        /// 准备数据源
        /// </summary>
        /// <returns>数据源</returns>
        public DataTable PrepareData()
        {
            DataTable dt = new DataTable();
            dt.Columns.Add("subject", typeof(string));
            dt.Columns.Add("score", typeof(float));
            dt.Rows.Add("数学", 80);
            dt.Rows.Add("语文", 89);
            dt.Rows.Add("英语", 97);
            dt.Rows.Add("物理", 78);
            dt.Rows.Add("化学", 76);
            return dt;
        }

        /// <summary>
        /// 图表绑定
        /// </summary>
        /// <param name="chartType">图表类型</param>
        public void ChartBind(SeriesChartType chartType)
        {
            DataTable dt = PrepareData();
            Chart1.Series["Series1"].Points.DataBind(dt.DefaultView, "subject", "score", "LegendText=subject,YValues=score,ToolTip=subject");
            Chart1.Series["Series1"].ChartType = chartType;//图表类型
            Chart1.DataBind();
        }

        /// <summary>
        /// 下拉框选择
        /// </summary>
        protected void ddlSelectType_SelectedIndexChanged(object sender, EventArgs e)
        {
            SeriesChartType chartType;
            string value = this.ddlSelectType.SelectedValue;
            switch (value)
            {
                case "Column": chartType = SeriesChartType.Column; break;//柱状图
                case "Pie": chartType = SeriesChartType.Pie; break;//饼图
                case "Line": chartType = SeriesChartType.Line; break;//折线图
                default: chartType = SeriesChartType.Column; break;
            }
            ChartBind(chartType);
        }

值得一提的是，只要指定了图表类别，绑定的代码共用一套，即可显示不同的图表效果。