当我尝试结果mysql进行写多选择时失败

Question

当我带数据库返回时，我使用了多选框，但无法在演示文稿中显示它。甚至出现在列表中，但未显示为选定状态。

var xml = XDocument.Parse(input);

var headerSection = xml.Descendants("Header");
var subHeaderSection = xml.Descendants("SubHeader");

var body = xml.Descendants("Body");
var activity = body.Descendants("Activity");
var position = body.Descendants("Position");
var positionAmouts = position.Descendants("PositionAmounts").Elements("PositionAmount");

var results = from h in headerSection
              from sh in subHeaderSection
              from a in activity              
              from po in position
              from pa in positionAmouts
              select new List<string>
              {
                  h.Element("Id").Value,
                  h.Element("OtherId").Value,
                  h.Element("SomeValue").Value,
                  sh.Element("SomeValue2").Value,
                  sh.Element("SomeValue3").Value,
                  a.Element("ActivityId").Value,
                  a.Element("ActivityValue").Value,
                  po.Element("PositionId").Value,
                  pa.Element("Amount1").Value,
                  pa.Element("Amount2").Value,
              }