public ActionResult ProblemList()
{
// 获取查询参数。
ProblemArchieveQueryParameter query = CreateProblemArchieveQueryParameter();
int page = 1;
if (!string.IsNullOrEmpty(Request.QueryString["page"]))
{
if (!int.TryParse(Request.QueryString["page"], out page))
{
page = 1;
}
}
query.EnablePageQuery = true;
query.PageQuery = new PageQueryParameter(page, ProblemListItemsPerPage);
// 执行分页查询。
IEnumerable <ProblemHandle> queryResult = ProblemArchieveManager.Default.QueryProblems(query);
List <ProblemBriefModel> problems = new List <ProblemBriefModel>();
foreach (ProblemHandle handle in queryResult)
{
problems.Add(ProblemBriefModel.FromProblemHandle(handle));
}
return(QueryResult(problems));
}
protected ProblemArchieveQueryParameter CreateProblemArchieveQueryParameter()
{
ProblemArchieveQueryParameter query = new ProblemArchieveQueryParameter();
if (!string.IsNullOrEmpty(Request.QueryString["title"]))
{
query.Title = Request.QueryString["title"];
query.QueryByTitle = true;
}
if (!string.IsNullOrEmpty(Request.QueryString["author"]))
{
query.Author = Request.QueryString["author"];
query.QueryByAuthor = true;
}
if (!string.IsNullOrEmpty(Request.QueryString["source"]))
{
query.Source = Request.QueryString["source"];
query.QueryBySource = true;
}
if (!string.IsNullOrEmpty(Request.QueryString["origin"]))
{
try
{
query.Origin = OJSystemConvert.ConvertFromString(Request.QueryString["origin"]);
query.QueryByOrigin = true;
}
catch (ArgumentException)
{ }
}
query.ContestId = -1;
query.QueryByContestId = true;
return(query);
}
public ActionResult ProblemListPages()
{
ProblemArchieveQueryParameter query = CreateProblemArchieveQueryParameter();
query.EnablePageQuery = true;
query.PageQuery = new PageQueryParameter(1, ProblemListItemsPerPage);
return(QueryResult(ProblemArchieveManager.Default.QueryPages(query)));
}
/// <summary>
/// 使用指定的查询对象查询题目句柄。
/// </summary>
/// <param name="query">为查询提供参数。</param>
/// <returns>一个列表，该列表中包含了所有的查询结果。</returns>
/// <exception cref="ArgumentNullException"/>
/// <exception cref="ArgumentOutOfRangeException"/>
public IList <ProblemHandle> QueryProblems(ProblemArchieveQueryParameter query)
{
if (query == null)
{
throw new ArgumentNullException(nameof(query));
}
if (query.QueryByTitle && query.Title == null)
{
throw new ArgumentNullException(nameof(query.Title));
}
if (query.QueryBySource && query.Source == null)
{
throw new ArgumentNullException(nameof(query.Source));
}
if (query.QueryByAuthor && query.Author == null)
{
throw new ArgumentNullException(nameof(query.Author));
}
if (query.Page == null)
{
throw new ArgumentNullException(nameof(query.Page));
}
if (query.Page.Page <= 0 || query.Page.EntriesPerPage <= 0)
{
throw new ArgumentOutOfRangeException(nameof(query.Page));
}
IQueryable <ProblemEntity> set = m_context.GetAllProblemEntities();
// 根据查询参数执行相应的查询，动态维护查询基础数据集。
if (query.QueryByTitle)
{
set = ProblemArchieveDataContext.QueryProblemEntitiesByTitle(set, query.Title);
}
if (query.QueryBySource)
{
set = ProblemArchieveDataContext.QueryProblemEntitiesBySource(set, query.Source);
}
if (query.QueryByAuthor)
{
set = ProblemArchieveDataContext.QueryProblemEntitiesByAuthor(set, query.Author);
}
// 执行分页。
set = set.Page(query.Page.Page, query.Page.EntriesPerPage);
List <ProblemHandle> handleList = new List <ProblemHandle>();
foreach (ProblemEntity entity in set)
{
handleList.Add(ProblemHandle.FromProblemEntity(entity));
}
return(handleList);
}
/// <summary>
/// 使用指定的查询对象计算满足条件的数据条目能填充多少页面。
/// </summary>
/// <param name="query">查询参数。</param>
/// <returns>满足查询条件的数据条目能填充的页面数量。</returns>
/// <exception cref="ArgumentNullException"/>
/// <exception cref="ArgumentException"/>
/// <exception cref="ArgumentOutOfRangeException"/>
public int QueryPages(ProblemArchieveQueryParameter query)
{
if (query == null)
{
throw new ArgumentNullException(nameof(query));
}
if (!query.EnablePageQuery)
{
throw new ArgumentException("给定的查询参数未启用分页。");
}
if (query.PageQuery.ItemsPerPage <= 0)
{
throw new ArgumentOutOfRangeException(nameof(query.PageQuery.ItemsPerPage));
}
return(m_factory.WithContext(context =>
{
IQueryable <ProblemEntity> set = DoQuery(context, query);
return set.GetPages(query.PageQuery.ItemsPerPage);
}));
}
/// <summary>
/// 使用指定的查询对象查询题目句柄。
/// </summary>
/// <param name="query">为查询提供参数。</param>
/// <returns>一个包含了所有的查询结果的查询结果对象。</returns>
/// <exception cref="ArgumentNullException"/>
/// <exception cref="ArgumentOutOfRangeException"/>
public ReadOnlyCollection <ProblemHandle> QueryProblems(ProblemArchieveQueryParameter query)
{
if (query == null)
{
throw new ArgumentNullException(nameof(query));
}
if (query.QueryByTitle && query.Title == null)
{
throw new ArgumentNullException(nameof(query.Title));
}
if (query.QueryBySource && query.Source == null)
{
throw new ArgumentNullException(nameof(query.Source));
}
if (query.QueryByAuthor && query.Author == null)
{
throw new ArgumentNullException(nameof(query.Author));
}
return(m_factory.WithContext(context =>
{
IQueryable <ProblemEntity> set = DoQuery(context, query);
// 对数据集进行排序以准备随时执行分页。
set = set.OrderBy(entity => entity.Id);
if (query.EnablePageQuery)
{
set = set.Page(query.PageQuery);
}
List <ProblemHandle> handles = new List <ProblemHandle>();
foreach (ProblemEntity ent in set)
{
handles.Add(ProblemHandle.FromProblemEntity(ent));
}
return new ReadOnlyCollection <ProblemHandle>(handles);
}));
}
private static IQueryable <ProblemEntity> DoQuery(ProblemDataContext context, ProblemArchieveQueryParameter query)
{
IQueryable <ProblemEntity> set = context.GetAllProblemEntities();
// 根据查询参数执行相应的查询，动态维护查询基础数据集。
if (query.QueryByTitle)
{
set = ProblemDataContext.QueryProblemEntitiesByTitle(set, query.Title);
}
if (query.QueryBySource)
{
set = ProblemDataContext.QueryProblemEntitiesBySource(set, query.Source);
}
if (query.QueryByAuthor)
{
set = ProblemDataContext.QueryProblemEntitiesByAuthor(set, query.Author);
}
if (query.QueryByOrigin)
{
set = ProblemDataContext.QueryProblemEntitiesByOrigin(set, (NativeOJSystem)query.Origin);
}
if (query.QueryByContestId)
{
set = ProblemDataContext.QueryProblemEntitiesByContestId(set, query.ContestId);
}
return(set);
}
