合并为绑定到Dropdown的ASP.NET列表对象

Question

我正在一个项目中，我有两个列表对象，需要使用XSLT将它们绑定到下拉列表。如何将两个列表对象合并在一起，然后将该对象转换为XSLT的XML，以填充下拉列表？

C＃对象

List<CarsViewModel> CarsViewModelList = new List<CarsViewModelList>();

List<TrucksViewModel> TrucksViewModelList = new List<TrucksViewModelList>();

合并两个对象以创建一个XML文件

XmlForm.DocumentContent = sXmlcarsTrucksViewModelList;
XmlForm.TransformSource = "/carstrucks.xslt";

XSLT文件     

          <select class="form-control" id="ddlDisease" name="ddlDisease">
            <option value="">Please choose a car type:</option>
            <xsl:for-each select="CottDiseaseViewModel">
              <option>
                <xsl:attribute name="value">
                  <xsl:value-of select="CarId"/>
                </xsl:attribute>
                <xsl:value-of select='CarName'/>
              </option>
            </xsl:for-each>
          </select>
        </div>
          <div class="form-group">

          <select class="form-control" id="ddlTrucks" name="ddlTrucks">
            <option value="">Please choose an Trucks type:</option>
            <xsl:for-each select="TrucksViewModelList">
              <option>
                <xsl:attribute name="value">
                  <xsl:value-of select="TruckId"/>
                </xsl:attribute>
                <xsl:value-of select='TruckName'/>
              </option>
            </xsl:for-each>
          </select>
        </div>
      </div>
      </div>