关键代码：

using System;
using System.Data;
using System.Windows.Forms;
using DevExPRess.XtraCharts;

namespace DevExpressChart
{
    public partial class winPieSeriesView : Form
    {
        public winPieSeriesView()
        {
            InitializeComponent();
        }
        private DataTable CreateChartData()
        {
            DataTable table = new DataTable("Table1");
            table.Columns.Add("Name", typeof(String));
            table.Columns.Add("Value", typeof(Int32)); 
            table.Rows.Add(new object[] { "A", 10 });
            table.Rows.Add(new object[] { "B", 20 });
            table.Rows.Add(new object[] { "C", 40 });
            table.Rows.Add(new object[] { "D", 20 });
            table.Rows.Add(new object[] { "E", 30 });
            return table;
        }
        private void winPieSeriesView_Load(object sender, EventArgs e)
        {
            BuilderDevChart();
        }
        private void BuilderDevChart()
        {
            Series _pieSeries = new Series("测试", ViewType.Pie);
            _pieSeries.ValueDataMembers[0] = "Value";
            _pieSeries.ArgumentDataMember = "Name";
            _pieSeries.DataSource = CreateChartData();
            chartControl1.Series.Add(_pieSeries);
            //----------------------------------------
            _pieSeries.LegendPointOptions.PointView = PointView.ArgumentAndValues;
            _pieSeries.SetPiePercentage();
        }
    }
}

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        /// <summary>
        /// 饼状Series设置成百分比显示
        /// </summary>
        /// <param name="series">Series</param>
        public static void SetPiePercentage(this Series series)
        {
            if (series.View is PieSeriesView)
            {
                ((PiePointOptions)series.PointOptions).PercentOptions.Valueaspercent = true;
                ((PiePointOptions)series.PointOptions).ValueNumericOptions.Format = NumericFormat.Percent;
                ((PiePointOptions)series.PointOptions).ValueNumericOptions.Precision = 0;
            }
        }

运行效果：

希望有所帮助！谢谢！