List 转换DataSet 出错:“DataSet 不支持 System.Nullable<>。”

[moumen]

/// <summary>
/// List<T> 转换成DataSet
/// </summary>
/// <typeparam name="T">对象</typeparam>
/// <param name="list">集合</param>
/// <returns>DataSet</returns>
public static DataSet ConvertToDataSet<T>(List<T> list)
{
if (list == null || list.Count <= 0)
{
return null;
}

DataSet ds = new DataSet();
DataTable dt = new DataTable(typeof(T).Name);
DataColumn column;
DataRow row;

System.Reflection.PropertyInfo[] myPropertyInfo = typeof(T).GetProperties(System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.Instance);

foreach (T t in list)
{
if (t == null)
{
continue;
}
row = dt.NewRow();

for (int i = 0, j = myPropertyInfo.Length; i < j; i++)
{
System.Reflection.PropertyInfo pi = myPropertyInfo[i];

string name = pi.Name;

if (dt.Columns[name] == null)
{
column = new DataColumn(name, pi.PropertyType);
dt.Columns.Add(column);
}
row[name] = pi.GetValue(t, null);
}
dt.Rows.Add(row);
}
ds.Tables.Add(dt);
return ds;
}

控制器代码
public JsonResult GetVillageName(string PartCode)
{
List<t_VillageManagement> dtlist = VillageManagementService.LoadEntities(c => c.Company == userInfo.Company && c.StatusCode == 1 && c.RegionalNumber == PartCode).ToList();

DataSet dt = ObjectConvert.ConvertToDataSet(dtlist);
//DataSet ds = new DataSet();
;
var jsonList = ObjectConvert.DataSetToJson(dt, "dt");
jsonList = Microsoft.JScript.GlobalObject.escape(jsonList);

return Json(new
{
Result = "OK",
Msg = jsonList
});
}