data structures - How to represent an extensible 2D array in C#? -


what need table can extended new columns (as rows) @ time. using datatable seems overkill don't need relational functionality nor data binding while need high speed of operation on big amounts of data (e.g. store million of rows columns , able add e.g. hundred of new columns quickly).

as best way seems pre-allocating simple 2d array of redundant size. there better ways?

there no inbuilt class provides functionality barring mentioned datatable, build own basic 1 without fuzz: 

public class table<t> {     private readonly list<list<t>> columns;      public table()     {         columns = new list<list<t>>();     }      public ienumerable<ienumerable<t>> columns => columns.select(c => c.select(r => r));     public ienumerable<ienumerable<t>> rows     {                 {             ienumerable<t> getrow(int index)             {                 foreach (var c in columns)                 {                     yield return c[index];                 }             }              (var row = 0; row < count; row++)             {                 yield return getrow(row);             }         }     }      public int count => columns.count == 0 ? 0 : columns[0].count;     public t this[int row, int column]     {                 {             return columns[column][row];         }         set         {             columns[column][row] = value;         }     }      public void addrow()     {         foreach (var c in columns)         {             c.add(default(t));         }     }      public void addrow(params t[] values)     {         if (values.length != columns.count)             throw new argumentexception();          (var column = 0; column < columns.count; column++)         {             columns[column].add(values[column]);         }     }      public void deleterow(int row)     {         foreach (var c in columns)         {             c.removeat(row);         }     }      public void addcolumn()     {         var newcolumn = new list<t>();          (var rows = 0; rows < count; rows++)         {             newcolumn.add(default(t));         }          columns.add(newcolumn);     }      public override string tostring()         => string.join(environment.newline, rows.select(c => string.join(";", c)));

if each column can hold own type, same code work making non generic , internal store list<list<object>>.

disclaimer: code hasn't been tested, looks bound have stupid bug...


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