Set lower bound and upper bound to get table rows

Question

I am using eos-sharp to get table rows in ASP.NET. By default in the table, I want to show the latest 10 records of the table. So I get them using:

GetTableRowsResponse tabledata = await eos.GetTableRows(new GetTableRowsRequest()
{
  json = true,
  code = contract,
  scope = contract,
  table = tables[0],
  reverse = true,
  lower_bound="0",
  upper_bound="-9",
  limit = 10
});

Now I need the next and previous 10 records. I tried for the next 10 records:

lower_bound="10",
upper_bound="-19",

But not getting records as expected. What values for lower bound and upper bound should be set? Please help

Answer 1

lower_bound and upper_bound set the range of primary key of items you want to retrieve. If you want to get first 10 items, then call get_table_rows by lower_bound and upper_bound with the value "", and it will return "next_key" in the result. Then pass the value of "next_key" to lower_bound (or if you want to call with "reverse": true, then next_key needs to be passed to upper_bound). You don't need to set both of lower_bound and upper_bound, because the number of items is deteremined by "limit": 10.

Updated(04/17/2021)

EosSharp is outdated. You need to add EosSharp to your project (instead of installing by NuGet), and modify it.

https://github.com/GetScatter/eos-sharp/blob/32bca887/EosSharp/EosSharp.Core/Api/v1/Definitions/EosApiMethodDef.t4#L252-L261

            Response = new Field[] 
            {
                new Field() { Name = "rows", Type = "List<object>"},
                new Field() { Name = "more", Type = "bool" },
                new Field() { Name = "next_key", Type = "string" } // add this line
            },
            GenericResponse = new Field[] 
            {
                new Field() { Name = "rows", Type = "List<TRowType>"},
                new Field() { Name = "more", Type = "bool" },
                new Field() { Name = "next_key", Type = "string" } // add this line
            }