How to creation two dimensional array in C#/LINQ.

HowToCreationTwoDimensionalArrayInCSharpLINQ.cs

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;

namespace ConsoleApplication21
{
    static class Program
    {
        public static T[,] ToTwoDimensionalArray<T>(this IEnumerable<IEnumerable<T>> enumerable)
        {
            var lines = enumerable.Select(inner => inner.ToArray()).ToArray();
            var columnCount = lines.Max(columns => columns.Length);
            var twa = new T[lines.Length, columnCount];
            for (var lineIndex = 0; lineIndex < lines.Length; lineIndex++)
            {
                var line = lines[lineIndex];
                for (var columnIndex = 0; columnIndex < line.Length; columnIndex++)
                {
                    twa[lineIndex, columnIndex] = line[columnIndex];
                }
            }
            return twa;
        }

        static void Main(string[] args)
        {
            var r = new Random();
            var results = Enumerable.Range(0, 100).
                Select(lineIndex => Enumerable.Range(0, 300).
                    Select(columnIndex => r.Next())).
                ToTwoDimensionalArray();

            Debug.Assert(results.GetLength(0) == 100);
            Debug.Assert(results.GetLength(1) == 300);
        }
    }
}

Here's a bit more concise version:

static class EnumerableExtensions
{
    public static T[,] To2DArray<T>(this IEnumerable<IEnumerable<T>> source)
    {
        var data = source
            .Select(x => x.ToArray())
            .ToArray();

        var res = new T[data.Length, data.Max(x => x.Length)];
        for (var i = 0; i < data.Length; ++i)
        {
            for (var j = 0; j < data[i].Length; ++j)
            {
                res[i,j] = data[i][j];
            }
        }

        return res;
    }
}