btcpayserver/BTCPayServer/Components/Pager/Default.cshtml

@model BasePagingViewModel

@{
    var pageSizeOptions = new [] { 50, 100, 250, 500 };
}

@if (Model.Total > pageSizeOptions.Min())
{
    <nav aria-label="..." class="w-100 clearfix">
        @if (Model.Total > Model.Count)
        {
            <ul class="pagination float-start">
                <li class="page-item @(Model.Skip == 0 ? "disabled" : null)">
                    <a class="page-link" tabindex="-1" href="@NavigatePages(-1, Model.Count)">&laquo;</a>
                </li>
                <li class="page-item disabled">
                    @if (Model.Total <= Model.Count)
                    {
                        <span class="page-link">
                            1–@Model.Total
                        </span>
                    }
                    else
                    {
                        <span class="page-link">
                            @(Model.Skip + 1)–@(Model.Skip + Model.Count), Total: @Model.Total
                        </span>
                    }
                </li>
                <li class="page-item @(Model.Total > (Model.Skip + Model.Count) ? null : "disabled")">
                    <a class="page-link" href="@NavigatePages(1, Model.Count)">&raquo;</a>
                </li>
            </ul>
        }

        @if (Model.Total >= pageSizeOptions.Min())
        {
            <ul class="pagination float-end">
                <li class="page-item disabled">
                    <span class="page-link">Page Size:</span>
                </li>
                @foreach (int pageSize in pageSizeOptions)
                {
                    if (Model.Total >= pageSize)
                    {
                        <li class="page-item @(Model.Count == pageSize ? "active" : null)">
                            <a class="page-link" href="@NavigatePages(0, pageSize)">@pageSize</a>
                        </li>
                    }
                }
            </ul>
        }
    </nav>
}
@{
    string NavigatePages(int prevNext, int count)
    {
        var skip = Model.Skip;
        if (prevNext == -1)
        {
            skip = Math.Max(0, Model.Skip - Model.Count);
        }
        else if (prevNext == 1)
        {
            skip = Model.Skip + count;
        }

        var query = new Dictionary<string, object>
        {
            { "searchTerm", Model.SearchTerm },
            { "timezoneOffset", Model.TimezoneOffset },
            { "skip", skip },
            { "count", count }
        };

        if (Model.PaginationQuery != null)
        {
            // merge both, prefering the `query` properties in case of duplicate keys
            query = query.Concat(Model.PaginationQuery)
                .GroupBy(e => e.Key)
                .ToDictionary(g => g.Key, g => g.First().Value);
        }

        return Url.Action(null, query);
    }
}