Question

我正在使用Page List ASP MVC插件向我的View添加分页，因为我的视图模型包含一个稍微失控的列表。但是，我遇到了一些问题。

视图模型包含另一个模型对象的List<T>。如果我对数据库进行一次查询，我就可以将此列表的数据类型从List<ZipCodeTerritory>更改为IPagedList<ZipCodeTerritory>，然后只需按照文档从查询中加载列表，如下所示： / LI>

查看模型

public IPagedList<ZipCodeTerritory> zipCodeTerritory { get; set; }

控制器

search.zipCodeTerritory = (from z in db.ZipCodeTerritory
                          where z.StateCode.Equals(search.searchState) &&
                                z.EffectiveDate >= effectiveDate
                         select z).ToList().ToPagedList(pageNumber, pageSize);

//This works but this only covers one of the three different searches that are 
//possibly from this Index page

然而，这提出了几个问题。首先，我无法使用C＃.clear使用的List方法。其次，更重要的是，如果我需要执行不同的搜索，我会多次点击数据库并将每个查询的结果添加到zipCodeTerritory列表中，我无法调用.addRange()方法。有谁知道如何将项目添加到IPagedList？

查看模型

public IPagedList<ZipCodeTerritory> zipCodeTerritory { get; set; }

控制器

foreach (var zip in zipArray)
{
    var item = from   z in db.ZipCodeTerritory
                where  z.ZipCode.Equals(zip) &&
                        z.EffectiveDate >= effectiveDate &&
                        z.IndDistrnId.Equals(search.searchTerritory) &&
                        z.StateCode.Equals(search.searchState)
                select z;
    search.zipCodeTerritory.AddRange(item); //This line throws the following exception:

    //PagedList.IPagedList<Monet.Models.ZipCodeTerritory>' does not contain a 
    //definition for 'AddRange' and no extension method 'AddRange' accepting a first 
    //argument of type 'PagedList.IPagedList<Monet.Models.ZipCodeTerritory>' could be 
    //found (are you missing a using directive or an assembly reference?)
}

我也尝试过在添加分页之前保留代码，然后尝试将List<T>强制转换为IPagedList<T>对象，但这也不起作用。这种方法可以解决我上面遇到的所有问题，所以如果有人知道如何简单地将List转换为IPagedList，那将非常感激。

查看模型

    public IPagedList<ZipCodeTerritory> pagedTerritoryList { get; set; }
    public List<ZipCodeTerritory> zipCodeTerritory { get; set; }

控制器

search.pagedTerritoryList = (IPagedList<ZipCodeTerritory>)search.zipCodeTerritory;

//This threw the following exception at runtime: 
//Unable to cast object of type  
//System.Collections.Generic.List'1[Monet.Models.ZipCodeTerritory]' to type 
//'PagedList.IPagedList'1[Monet.Models.ZipCodeTerritory]'.

Answer 1

要将各种方法结合在一起，你可能应该做这样的事情（根据你的第一个例子）：

var mySearch = (from z in db.ZipCodeTerritory
                      where z.StateCode.Equals(search.searchState) &&
                            z.EffectiveDate >= effectiveDate
                     select z).ToList();

// Other searches, whatever; use mySearch.AddRange() here

search.zipCodeTerritory = mySearch.ToPagedList(pageNumber, pageSize);

无法添加到IPagedList对象或将List <t>传输到IPagedList <t> </t> </t>

1 个答案: