我有用于计算分页的 Controller 。但是我有 13 个不同的 Controller 。因此，在每个 Controller 中编写该计算将是乏味的。
这是完整的方法:
[Route("sort/{SortColumn}/{SortOrder?}", Name = "Sort-Product")]
[Route("page/{Page:int}/{SortColumn}/{SortOrder?}", Name = "Paging-Product")]
[Route("search/{SearchString}")]
[Route("index")]
public ActionResult Index(string searchString, string filter, string currentFilter, string sortColumn, string sortOrder, int? page)
{
IOrderedQueryable<Product> entities = (IOrderedQueryable<Product>)db.FilteredProducts;
if (searchString != null) page = 1; else searchString = currentFilter;
if (filter != null) {
string[] filters = filter.Split(new char[] { '.' });
filter = "";
// filter on form
if (filters.Length > 0 && !String.IsNullOrEmpty(filters[0])) {
FormLibraryEntry formEntry = FormLibraryController.GetFormLibraryEntry(filters[0], StateHelper.GetSchema());
if (formEntry != null) {
entities = (IOrderedQueryable<Product>)entities.Where(
s => s.FormName == formEntry.Id
);
AddFixedNotification(String.Format(Resources.Entity.Environment.FilteredByFormMessage, formEntry.Name));
filter += filters[0];
}
}
// filter on design template
if (filters.Length > 1 && !String.IsNullOrEmpty(filters[1])) {
var designEntry = DesignTemplateController.GetTemplateLibraryEntry(filters[1], StateHelper.GetSchema());
if (designEntry != null) {
entities = (IOrderedQueryable<Product>)entities.Where(
s => s.TemplateName == designEntry.Id
);
AddFixedNotification(String.Format(Resources.Entity.Environment.FilteredByDesignTemplateMessage, designEntry.Name));
filter += "." + filters[1];
}
}
}
if (!String.IsNullOrEmpty(searchString)) {
entities = (IOrderedQueryable<Product>)entities.Where(
s => s.Name.ToUpper().Contains(searchString.ToUpper())
|| (!String.IsNullOrEmpty(s.FormName) && s.FormName.ToUpper().Contains(searchString.ToUpper()))
|| (!String.IsNullOrEmpty(s.UrlName) && s.UrlName.ToUpper().Contains(searchString.ToUpper()))
);
AddFixedNotification(String.Format(Resources.Entity.Environment.FilteredBySearchTermMessage, searchString));
}
switch (sortColumn) {
case "id":
entities = (sortOrder == "desc") ? entities.OrderByDescending(s => s.Id) : entities.OrderBy(s => s.Id);
break;
case "name":
entities = (sortOrder == "desc") ? entities.OrderByDescending(s => s.Name) : entities.OrderBy(s => s.Name);
break;
case "enabled":
entities = (sortOrder == "desc") ? entities.OrderByDescending(s => s.IsEnabled) : entities.OrderBy(s => s.IsEnabled);
break;
case "formname":
entities = (sortOrder == "desc") ? entities.OrderByDescending(s => s.FormName) : entities.OrderBy(s => s.FormName);
break;
case "design":
entities = (sortOrder == "desc") ? entities.OrderByDescending(s => s.TemplateName) : entities.OrderBy(s => s.TemplateName);
break;
case "urlname":
entities = (sortOrder == "desc") ? entities.OrderByDescending(s => s.UrlName) : entities.OrderBy(s => s.UrlName);
break;
case "forms":
entities = (sortOrder == "desc") ? entities.OrderByDescending(s => s.SubmittedForms.Count()) : entities.OrderBy(s => s.SubmittedForms.Count());
break;
case "modified":
entities = (sortOrder == "desc") ? entities.OrderByDescending(s => s.ModificationDate) : entities.OrderBy(s => s.ModificationDate);
break;
default:
sortColumn = "name";
sortOrder = "";
entities = (sortOrder == "desc") ? entities.OrderByDescending(s => s.Name) : entities.OrderBy(s => s.Name);
break;
}
ViewBag.SortColumn = sortColumn;
ViewBag.SortOrder = sortOrder == "desc" ? "desc" : "";
ViewBag.SearchString = searchString;
ViewBag.Filter = filter;
int pageSize = StateHelper.GetPageSize();
int pageNumber = StateHelper.HasPageSizeChanged ? 1 : (page ?? 1);
object selectionProduct = ModelHelper.GetSelectedModelId("Product");
if (selectionProduct != null) {
IEnumerable<IEnumerable<Product>> pp = entities.Partition(pageSize);
int calculatedPage = 0;
bool found = false;
foreach (var item in pp) {
calculatedPage++;
IEnumerable<Product> inner = item as IEnumerable<Product>;
foreach (var product in inner) {
if (product.Id == (int)selectionProduct) {
found = true;
ViewBag.selectedRowProduct = product.Id;
break;
}
}
if (found)
break;
}
if (found)
pageNumber = calculatedPage;
}
return View(entities.ToPagedList(pageNumber, pageSize));
}
但这是计算的部分:
object selectionProduct = ModelHelper.GetSelectedModelId("Product");
if (selectionProduct != null) {
IEnumerable<IEnumerable<Product>> pp = entities.Partition(pageSize);
int calculatedPage = 0;
bool found = false;
foreach (var item in pp) {
calculatedPage++;
IEnumerable<Product> inner = item as IEnumerable<Product>;
foreach (var product in inner) {
if (product.Id == (int)selectionProduct) {
found = true;
ViewBag.selectedRowProduct = product.Id;
break;
}
}
if (found)
break;
}
if (found)
pageNumber = calculatedPage;
}
所以我尝试构建这样的辅助方法:
public static bool FindPage(Type T, object modelId, IEnumerable<Type> entities, int pageSize, int calculatedPage, int? id)
{
if (modelId != null) {
calculatedPage = 0;
IEnumerable<IEnumerable<T>> pp = entities.Partition(pageSize);
int page = 0;
bool found = false;
foreach (var item in pp) {
page++;
IEnumerable<Type> inner = item as IEnumerable<Type>;
foreach (var product in inner) {
if (id == (int)modelId) {
found = true;
break;
}
}
if (found)
break;
}
if (found)
calculatedPage = page;
else
calculatedPage = 0;
return found;
}
return false;
}
但是我得到这个错误:
The type or namespace name 'T' could not be found (are you missing a using directive or an assembly reference?)
谢谢
最佳答案
尝试:
public static bool FindPage<T>(object modelId, IEnumerable<T> entities, int pageSize, int calculatedPage, int? id)
{
if (modelId != null) {
calculatedPage = 0;
IEnumerable<IEnumerable<T>> pp = entities.Partition(pageSize);
int page = 0;
bool found = false;
foreach (var item in pp) {
page++;
IEnumerable<T> inner = item as IEnumerable<T>;
foreach (var product in inner) {
if (id == (int)modelId) {
found = true;
break;
}
}
if (found)
break;
}
if (found)
calculatedPage = page;
else
calculatedPage = 0;
return found;
}
return false;
}
关于c# - 编写分页的通用方法，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/31399889/