egwcorelib/EgwCoreLib.Razor/DataPager.razor.cs

using Microsoft.AspNetCore.Components;

namespace EgwCoreLib.Razor
{
    public partial class DataPager : ComponentBase
    {
        #region Public Enums

        public enum ObjSize
        {
            small,
            standard,
            large
        }

        #endregion Public Enums

        #region Public Properties

        /// <summary>
        /// Num pagina correntemente selezioanta
        /// </summary>
        [Parameter]
        public int currPage
        {
            get
            {
                return _numPage;
            }
            set
            {
                bool doReport = !_numPage.Equals(value);
                if (doReport)
                {
                    _numPage = value;
                    reportChangePage();
                }
            }
        }

        /// <summary>
        /// Dimensione controlli x resize
        /// </summary>
        [Parameter]
        public ObjSize DisplSize { get; set; } = ObjSize.standard;

        /// <summary>
        /// Export (csv) abilitato
        /// </summary>
        [Parameter]
        public bool exportEnabled { get; set; } = false;

        /// <summary>
        /// Evento richiesta export
        /// </summary>
        [Parameter]
        public EventCallback<int> exportRequested { get; set; }

        /// <summary>
        /// Filename x export
        /// </summary>
        [Parameter]
        public string fileName { get; set; } = "";

        /// <summary>
        /// Evento cambio pagina nel paginatore
        /// </summary>
        [Parameter]
        public EventCallback<int> numPageChanged { get; set; }

        /// <summary>
        /// Massimo numero di pagine da mostrare (x display piccoli)
        /// </summary>
        [Parameter]
        public int NumPages { get; set; } = 10;


        /// <summary>
        /// Test btn vai a inizio
        /// </summary>
        [Parameter]
        public string TxtStart { get; set; } = "Start";
        /// <summary>
        /// Test btn vai a fine
        /// </summary>
        [Parameter]
        public string TxtEnd { get; set; } = "End";
        /// <summary>
        /// Test btn vai a PrevBlock
        /// </summary>
        [Parameter]
        public string TxtPrev { get; set; } = "Prev";
        /// <summary>
        /// Test btn vai a NextBlock
        /// </summary>
        [Parameter]
        public string TxtNext{ get; set; } = "Next";

        /// <summary>
        /// PageSize = Num record da mostrare cambiato
        /// </summary>
        [Parameter]
        public EventCallback<int> numRecordChanged { get; set; }

        /// <summary>
        /// Attuale PageSize
        /// </summary>
        [Parameter]
        public int PageSize
        {
            get
            {
                return _numRecord;
            }
            set
            {
                bool doReport = !_numRecord.Equals(value);
                if (doReport)
                {
                    _numRecord = value;
                    reportChange();
                }
            }
        }

        /// <summary>
        /// Elenco dei PageSize ammessi
        /// </summary>
        [Parameter]
        public List<int> PageSizeList { get; set; } = new List<int>()
        {
            5,10,25,50,100
        };

        /// <summary>
        /// Fase di loading
        /// </summary>
        [Parameter]
        public bool showLoading
        {
            get
            {
                return _showLoading;
            }
            set
            {
                if (value)
                {
                    Random random = new Random();
                    percLoading = random.Next(30, 90);
                }
                else
                {
                    percLoading = 5;
                }
                _showLoading = value;
            }
        }

        /// <summary>
        /// Totale record da mostrare
        /// </summary>
        [Parameter]
        public int totalCount { get; set; } = 0;

        #endregion Public Properties

        #region Public Methods

        public void resetCurrPage()
        {
            //await Task.Delay(1);
            currPage = 1;
        }

        #endregion Public Methods

        #region Protected Fields

        protected bool _showLoading = false;

        protected string exportDir = $"{Directory.GetCurrentDirectory()}\\temp";

        #endregion Protected Fields

        #region Protected Properties

        protected int _numPage { get; set; } = 1;

        protected int _numRecord { get; set; } = 10;

        protected bool fileExist
        {
            get
            {
                return File.Exists(fullPath);
            }
        }

        protected string fullPath
        {
            get => $"{exportDir}\\{fileName}";
        }

        private string cssSize
        {
            get
            {
                string answ = "";
                switch (DisplSize)
                {
                    case ObjSize.small:
                        answ = "small";
                        break;
                    case ObjSize.standard:
                        break;
                    case ObjSize.large:
                        answ = "large";
                        break;
                    default:
                        break;
                }
                return answ;
            }
        }

        protected int percLoading { get; set; } = 0;

        #endregion Protected Properties

        #region Protected Methods

        protected string cssActive(int numPage)
        {
            string answ = "";
            if (numPage == currPage)
            {
                answ = "active";
            }
            return answ;
        }

        protected override async Task OnInitializedAsync()
        {
            await Task.Run(() => showLoading = false);
        }

        protected void PaginationItemClick(int page)
        {
            currPage = page;
        }

        #endregion Protected Methods

        #region Private Properties

        private int endPage
        {
            get
            {
                int answ = startPage + NumPages -1;
                answ = answ < LastPage ? answ : LastPage;
                return answ;
            }
        }

        private int LastPage
        {
            get
            {
                return Math.Max((int)Math.Ceiling(totalCount / (double)PageSize), 1);
            }
        }

        private int nextBlock
        {
            get
            {
                int answ = currPage + NumPages;
                answ = answ < LastPage ? answ : LastPage;
                return answ;
            }
        }

        private int prevBlock
        {
            get
            {
                int answ = currPage - NumPages;
                answ = answ > 0 ? answ : 1;
                return answ;
            }
        }

        /// <summary>
        /// calcola un set 1 .. NumPages centrato sulla pagina corrente...
        /// </summary>
        private int startPage
        {
            get
            {
                int answ = ((int)((currPage -1) / NumPages) ) * NumPages + 1;
                answ = answ > 0 ? answ : 1;
                return answ;
            }
        }

        #endregion Private Properties

        #region Private Methods

        private void reportChange()
        {
            numRecordChanged.InvokeAsync(PageSize);
        }

        private void reportChangePage()
        {
            numPageChanged.InvokeAsync(currPage);
        }

        private async Task requestSave()
        {
            showLoading = true;
            await Task.Delay(1);
            await exportRequested.InvokeAsync(currPage);
            showLoading = false;
        }

        #endregion Private Methods
    }
}