后台代码：
1 构造selectlist，通过viewbag传到前端
var assetNameList = middleResult.Select(p=>p.AssetName).Distinct();
SelectList selList1 = new SelectList(assetNameList);
ViewBag.assetNameList = selList1;
var departmentNameList = middleResult.Select(p=>p.DepartmentName).Distinct();
SelectList selList2 = new SelectList(departmentNameList);
ViewBag.departmentNameList = selList2;
前端代码：
2 前端获取selectlist，"assetName"和"departmentName"为form表单提交数据时的参数名
@Html.DropDownList("assetName", ViewBag.assetNameList as SelectList)
@Html.DropDownList("departmentName", ViewBag.departmentNameList as SelectList)