ASP.Net MVC+Data Table實現分頁+排序功能的方法

@using BCMS.BusinessLogic
@using BCMS.BusinessLogic.Models
@model List<BusCaptainObj>
<table id="tblData" class="table table-striped">
 <thead>
 <tr class="data-list">
 <th style="width:10%;">@Html.DisplayNameFor(model => model.First().PersNo)</th>
 <th style="width:30%;">@Html.DisplayNameFor(model => model.First().Personnel_Name)</th>
 <th style="width:20%;">@Html.DisplayNameFor(model => model.First().Position)</th>
 <th style="width:20%;">@Html.DisplayNameFor(model => model.First().Interchange)</th>
 <th style="width:20%;">Action</th>
 </tr>
 </thead>
</table>
@section scripts {
 <script type="text/javascript">
 @{
 var columns = DataTableHelper.DisplayColumns<BusCaptainObj>();
 }
 $(document).ready(function () {
 $('#tblData').dataTable({
 "processing": true,
 "serverSide": true,
 "searching": false,
 "stateSave": true,
 "oLanguage": { "sInfoFiltered": "" },
 "ajax": {
 "url": @Url.Action("GetJsonData"),
 "type": "GET"
 },
 "columns": [
 { "data": "@columns[0]" },
 { "data": "@columns[1]" },
 { "data": "@columns[2]" },
 { "data": "@columns[3]" },
 {
 "data": "@columns[0]",
 "orderable": false,
 "searchable": false,
 "render": function (data, type, full, meta) {
 if (type === 'display') {
 return GetDetailButton("/BusCaptain/Detail?bcId=", data) + GetInfoButton("/Telematics?bcId=", data, "Performance");
 } else { return data; }
 }
 }
 ],
 "order": [[0, "asc"]]
 });
 });
 </script>
}

public ActionResult GetJsonData(int draw, int start, int length)
{
 string search = Request.QueryString[DataTableQueryString.Searching];
 string sortColumn = "";
 string sortDirection = "asc";
 if (Request.QueryString[DataTableQueryString.OrderingColumn] != null)
 {
 sortColumn = GetSortColumn(Request.QueryString[DataTableQueryString.OrderingColumn]);
 }
 if (Request.QueryString[DataTableQueryString.OrderingDir] != null)
 {
 sortDirection = Request.QueryString[DataTableQueryString.OrderingDir];
 }
 DataTableData dataTableData = new DataTableData();
 dataTableData.draw = draw;
 int recordsFiltered = 0;
 dataTableData.data = BusCaptainService.Instance.SearchMyBuscaptains(User.Identity.Name, out recordsFiltered, start, length, sortColumn, sortDirection, search).Data;
 dataTableData.recordsFiltered = recordsFiltered;
 return Json(dataTableData, JsonRequestBehavior.AllowGet);
}
public string GetSortColumn(string sortColumnNo)
{
 var name = DataTableHelper.SoringColumnName<BusCaptainObj>(sortColumnNo);
 return name;
}
public class DataTableData
{
 public int draw { get; set; }
 public int recordsFiltered { get; set; }
 public List<BusCaptainObj> data { get; set; }
}

class XXX{
...
 [DisplayColumn(0)]
 [SortingColumn(0)]
 public int? A { get; set; }
 [DisplayColumn(1)]
 [SortingColumn(1)]
 public string B { get; set; }
...
}

public class SortingColumnAttribute : Attribute
{
 public int Index { get; }
 public SortingColumnAttribute(int index)
 {
 Index = index;
 }
}
public class DisplayColumnAttribute : Attribute
{
 public int Index { get; }
 public DisplayColumnAttribute(int index)
 {
 Index = index;
 }
}
public static class DataTableQueryString
{
 public static string OrderingColumn = "order[0][column]";
 public static string OrderingDir = "order[0][dir]";
 public static string Searching = "search[value]";
}
public static class DataTableHelper
{
 public static IList<string> DisplayColumns<T>()
 {
 var result = new Dictionary<int, string>();
 var props = typeof(T).GetProperties();
 foreach (var propertyInfo in props)
 {
 var propAttr =
 propertyInfo
 .GetCustomAttributes(false)
 .OfType<DisplayColumnAttribute>()
 .FirstOrDefault();
 if (propAttr != null)
 {
 result.Add(propAttr.Index,propertyInfo.Name);
 }
 }
 return result.OrderBy(x => x.Key).Select(x => x.Value).ToList();
 }
 public static string SoringColumnName<T>(string columnIndex)
 {
 int index;
 if (!int.TryParse(columnIndex, out index))
 {
 throw new ArgumentOutOfRangeException();
 }
 return SoringColumnName<T>(index);
 }
 public static string SoringColumnName<T>(int index)
 {
 var props = typeof(T).GetProperties();
 foreach (var propertyInfo in props)
 {
 var propAttr =
 propertyInfo
 .GetCustomAttributes(false)
 .OfType<SortingColumnAttribute>()
 .FirstOrDefault();
 if (propAttr != null && propAttr.Index == index)
 {
 return propertyInfo.Name;
 }
 }
 return "";
 }
}

...
var query = context.BusCaptains
 .Where(x => ...)
 .OrderByEx(sortDirection, sortField)
 .Skip(start)
 .Take(pageSize);
...

...
public static IQueryable<T> OrderByEx<T>(this IQueryable<T> q, string direction, string fieldName)
 {
 try
 {
 var customProperty = typeof(T).GetCustomAttributes(false).OfType<ColumnAttribute>().FirstOrDefault();
 if (customProperty != null)
 {
 fieldName = customProperty.Name;
 }
 var param = Expression.Parameter(typeof(T), "p");
 var prop = Expression.Property(param, fieldName);
 var exp = Expression.Lambda(prop, param);
 string method = direction.ToLower() == "asc" ? "OrderBy" : "OrderByDescending";
 Type[] types = new Type[] {q.ElementType, exp.Body.Type};
 var mce = Expression.Call(typeof(Queryable), method, types, q.Expression, exp);
 return q.Provider.CreateQuery<T>(mce);
 }
 catch (Exception ex)
 {
 _log.ErrorFormat("error form OrderByEx.");
 _log.Error(ex);
 throw ;
 }
 }
...