This is a sample of code how to Insert and delete item from container in Axapta. This code you can apply in form or report for your purpose.
static void Datatypes_container_functions(Args _args)
{
container con;
;
// conins - Insert values to the container
con = conins(con, 1, "Toyota");
con = conins(con, 2, 20);
con = conins(con, 3, 2200.20);
con = conins(con, 4, "BMW");
con = conins(con, 5, 12);
con = conins(con, 6, 3210.44);
// condel - Delete the third and the fourth element
// from the container
con = condel(con, 3, 2);
// conpeek - Read values from the container
info(conpeek(con,1));
info(conpeek(con,2));
info(conpeek(con,3));
info(conpeek(con,4));
// connull - Reset the container
con = connull();
// conlen - Get the length of the container
info(strfmt("Length: %1",conlen(con)));
}