MVC3 带查询的分页Helper

接上篇mvc3 分页Helper.

　　带查询的分页Helper是在上一篇分页的基础上来的。下面看代码：

　　首先，在System.Web.Mvc命名空间下的自定义类HtmlPage下面添加一个用于处理“查询字典”的方法UrlGetParameter。　　

　　

/// <summary>
        /// 根据查询字典，拼写查询参数
        /// </summary>
        /// <param name="parameters"></param>
        /// <returns></returns>
        public static string UrlGetParameter(Dictionary<string,string> parameters)
        {
            if (parameters != null && parameters.Count > 0)
            {
                StringBuilder sb = new StringBuilder();
                foreach (var item in parameters)
                {
                    sb.Append("&"+item.Key.ToLower()+"="+item.Value);
                }
                return sb.ToString();
            }
            else
            {
                return "";
            }
        }

　　然后，修改HtmlPage类下面的ShowPageNavigate方法如下：

　　

 public static HtmlString ShowPageNavigate(this HtmlHelper htmlHelper, int currentPage, int pageSize, int totalCount,Dictionary<string,string> parameters=null)
        {
            var redirectTo = htmlHelper.ViewContext.RequestContext.HttpContext.Request.Url.AbsolutePath;
            pageSize = pageSize == 0 ? 3 : pageSize;
            var totalPages = Math.Max((totalCount + pageSize - 1) / pageSize, 1); //总页数
            string searchCode = string.Empty;
            if (parameters!=null)
            {
                searchCode = UrlGetParameter(parameters);
            }
            var output = new StringBuilder();
            if (totalPages > 1)
            {                
                    output.AppendFormat("<a class='pageLink' href='{0}?pageIndex=1&pageSize={1}{2}'>首页</a> ", redirectTo, pageSize,searchCode);                
                if (currentPage > 1)
                {//处理上一页的连接
                    output.AppendFormat("<a class='pageLink' href='{0}?pageIndex={1}&pageSize={2}{3}'>上一页</a> ", redirectTo, currentPage - 1, pageSize,searchCode);
                }                

                output.Append(" ");
                int currint = 5;
                for (int i = 0; i <= 10; i++)
                {//一共最多显示10个页码，前面5个，后面5个
                    if ((currentPage + i - currint) >= 1 && (currentPage + i - currint) <= totalPages)
                    {
                        if (currint == i)
                        {//当前页处理                            
                            output.AppendFormat("<a class='cpb' href='{0}?pageIndex={1}&pageSize={2}{3}'>{4}</a> ", redirectTo, currentPage, pageSize, searchCode, currentPage);
                        }
                        else
                        {//一般页处理
                            output.AppendFormat("<a class='pageLink' href='{0}?pageIndex={1}&pageSize={2}{4}'>{3}</a> ", redirectTo, currentPage + i - currint, pageSize, currentPage + i - currint,searchCode);
                        }
                    }
                    output.Append(" ");
                }
                if (currentPage < totalPages)
                {//处理下一页的链接
                    output.AppendFormat("<a class='pageLink' href='{0}?pageIndex={1}&pageSize={2}{3}'>下一页</a> ", redirectTo, currentPage + 1, pageSize,searchCode);
                }
                
                output.Append(" ");
                if (currentPage != totalPages)
                {
                    output.AppendFormat("<a class='pageLink' href='{0}?pageIndex={1}&pageSize={2}{3}'>末页</a> ", redirectTo, totalPages, pageSize,searchCode);
                }
                output.Append(" ");
            }
            output.AppendFormat("<label>第{0}页 / 共{1}页</label>", currentPage, totalPages);//这个统计加不加都行

            return new HtmlString(output.ToString());
        }

　　其次，还要将"查询字典"属性添加到PageInfo字典中。　　

　　

public class PagerInfo
    {
        public int RecordCount { get; set; }

        public int CurrentPageIndex { get; set; }

        public int PageSize { get; set; }
        //放置查询参数
        public Dictionary<string, string> SearchParameter { get; set; }
    }

　　最后，就要写View和Controller里的内容的。先看Controller的代码，添加一个用于回发的Action即（Index）,把get,post的Action都写出来吧。

　　

//get /News/Index/?
        public ActionResult Index(int? pageSize, int? pageIndex, string pauthor, string ptitle)
        {
            Dictionary<string, string> pagerParamers = new Dictionary<string, string>();
            int pageIndex1 = pageIndex ?? 1;
            int pageSize1 = pageSize ?? 5;
            //从数据库在取得数据，并返回总记录数
            var temp = newsSer.LoadEntities(c => c.del == false).AsQueryable();
            PagerInfo pager = new PagerInfo();
            pager.CurrentPageIndex = pageIndex1;
            pager.PageSize = pageSize1;
            if (!string.IsNullOrEmpty(pauthor))
            {
                pagerParamers.Add("pauthor", pauthor);
                temp = temp.Where(c => c.author.Contains(pauthor)).AsQueryable();
            }
            if (!string.IsNullOrEmpty(ptitle))
            {
                pagerParamers.Add("ptitle", ptitle);
                temp=temp.Where(c => c.title.Contains(ptitle)).AsQueryable();
            }
            pager.RecordCount = temp.Count();            
            pager.SearchParameter = pagerParamers;
            temp=temp.OrderByDescending(c => c.id).Skip((pageIndex1 - 1) * pageSize1).Take(pageSize1).AsQueryable();     
            PagerQuery<PagerInfo, IQueryable<news>> query = new PagerQuery<PagerInfo, IQueryable<news>>(pager, temp);
            return View(query);
        }

        //Post /News/Index/?
        [HttpPost]
        public ActionResult Index(FormCollection form)
        {
            try
            {
                string pauthor = form["pauthor"];
                string ptitle = form["ptitle"];
                Dictionary<string, string> pagerParams = new Dictionary<string, string>();
                int pageIndex = 1;
                int pageSize = 5;
                PagerInfo pager = new PagerInfo();
                pager.CurrentPageIndex = pageIndex;
                pager.PageSize = pageSize;
                //从数据库在取得数据，并返回总记录数
                var temp = newsSer.LoadEntities(c => c.author.Contains(pauthor)).AsQueryable();
                if (!string.IsNullOrEmpty(pauthor))
                {
                    pagerParams.Add("pauthor", pauthor);
                    temp = temp.Where(c => c.author.Contains(pauthor) && c.del == false).AsQueryable();
                }
                if (!string.IsNullOrEmpty(ptitle))
                {
                    pagerParams.Add("ptitle", ptitle);
                    temp = temp.Where(c => c.title.Contains(ptitle)).AsQueryable();
                }
                pager.RecordCount = temp.Count();
                pager.SearchParameter = pagerParams;
                temp = temp.OrderBy(c => c.id).Skip((pageIndex - 1) * pageSize).Take(pageSize);
                PagerQuery<PagerInfo, IQueryable<news>> query = new PagerQuery<PagerInfo, IQueryable<news>>(pager, temp);
                return View(query);
            }
            catch
            {
                return View();
            }
        }

　　接下来，看一下View中的代码：　　

　　

 @using (Html.BeginForm("Index", "News", FormMethod.Post, new { @class = "well" }))
                {                                 
                    <input type="text" id="pauthor" class="search-query" name="pauthor" placeholder="作者" /> 
                    <input type="text" id="ptitle" class="search-query" name="ptitle" placeholder="标题" />
                    <input type="submit" class="btn" value="查询" />                                   
                }
                <table style="margin-top: 10px;">
                    <thead>
                        <tr>
                            <th width="25">
                                <input class="select-all" name="" type="checkbox" value="" />
                            </th>
                            <th>
                                作者
                            </th>
                            <th>
                                新闻标题
                            </th>
                            <th>
                                创建时间
                            </th>
                            <th>
                                操作
                            </th>
                        </tr>
                    </thead>
                    <tbody>
                        @foreach (var item in Model.EntityList)
                        { 
                            <tr>
                                <td class="checkBox">
                                    <input name="ids[]" type="checkbox" value="" />
                                </td>
                                <td>
                                    @item.author
                                </td>
                                <td>
                                    @item.title
                                </td>
                                <td>
                                    @item.ctime
                                </td>
                                <td>
                                    @Html.ActionLink("编辑", "Edit", new { id = item.id }) |
                                    @Html.ActionLink("删除", "Delete", new { id = item.id })
                                </td>
                            </tr>
                        }
                        @*分页*@
                        <tr class="">
                            <td colspan="5" align="center" class="paginator">
                                <span>
                                    @Html.ShowPageNavigate(Model.Pager.CurrentPageIndex, Model.Pager.PageSize, Model.Pager.RecordCount, Model.Pager.SearchParameter)
                                </span>
                            </td>
                        </tr>
                    </tbody>
                </table>

　　分页的样式见上一节"MVC# 分页Helper"，查询表单的样式，就不再列出了。

　　最后再补充一下，如果在查询时依然想要使用以前的PageSize(当然了，这里的PageSize是固定的)，可以在进行请求时将pageSize保存在ViewBag中，然后在View中将它保存在表单的隐藏域中，这样就可以使用设置好的pageSize了。（页面跳转、上n页、下n页，这里就不列出来了。）

　　最终的效果图：　　

　　

　　ok.大功告成！