ChartPieSeries cps = new ChartPieSeries();
cps.name = "pie demo";
cps.radius = 90;
cps.startAngle = 300;
cps.type = "pie"; 

ChartSeriesData csd_pc = new ChartSeriesData();
csd_pc.name = "电脑";
csd_pc.value = "23";

ChartSeriesData csd_phone = new ChartSeriesData();
csd_phone.name = "手机";
csd_phone.value = "88";

List<object> data = new List<object>();
data.Add(csd_pc);
data.Add(csd_phone);

cps.data = data; 

List<string> legend = new List<string>(4);
legend.Add("电脑");
legend.Add("手机"); 

List<ChartPieSeries> cpss = new List<ChartPieSeries>();
cpss.Add(cps); 

string str = ChartOpertation.ChartPieDataProcess(cpss, legend, true, "pie demo", "subtext", true);