pagination net core code example
Example 1: how manage pagination ef core
public static class PaginationService
{
public static async Task<Pagination<T>> GetPagination<T>(IQueryable<T> query, int page, string orderBy, bool orderByDesc, int pageSize) where T : class
{
Pagination<T> pagination = new Pagination<T>
{
TotalItems = query.Count(),
PageSize = pageSize,
CurrentPage = page,
OrderBy = orderBy,
OrderByDesc = orderByDesc
};
int skip = (page - 1) * pageSize;
var props = typeof(T).GetProperties();
var orderByProperty = props.FirstOrDefault(n => n.GetCustomAttribute<SortableAttribute>()?.OrderBy == orderBy);
if (orderByProperty == null)
{
throw new Exception($"Field: '{orderBy}' is not sortable");
}
if (orderByDesc)
{
pagination.Result = await query
.OrderByDescending(x => orderByProperty.GetValue(x))
.Skip(skip)
.Take(pageSize)
.ToListAsync();
return pagination;
}
pagination.Result = await query
.OrderBy(x => orderByProperty.GetValue(x))
.Skip(skip)
.Take(pageSize)
.ToListAsync();
return pagination;
}
}
Example 2: how manage pagination ef core
[HttpGet]
public async Task<IActionResult> GetUsers([FromQuery] string orderBy, [FromQuery] bool orderByDesc, [FromQuery] int page, [FromQuery] int size)
{
var query = _context.User.AsQueryable();
try
{
var list = await PaginationService.GetPagination(query, page, orderBy, orderByDesc, size);
return new JsonResult(list);
}
catch (Exception e)
{
return new BadRequestObjectResult(e.Message);
}
}