what is the best way to split string in c#

Question

I have a string that look like that "a,b,c,d,e,1,4,3,5,8,7,5,1,2,6.... and so on. I am looking for the best way to split it and make it look like that:

a                     b              c              d              e

1                     4              3               5              8

7                      5              1              2               6

Answer 1

Assuming, that you have a fix number of columns (5):

string Input = "a,b,c,d,e,11,45,34,33,79,65,75,12,2,6";
int i = 0;
string[][] Result = Input.Split(',').GroupBy(s => i++/5).Select(g => g.ToArray()).ToArray();

First I split the string by , character, then i group the result into chunks of 5 items and select those chunks into arrays.

Result:

a    b    c    d    e
11   45   34  33   79
65   75   12   2    6

to write that result into a file you have to

using (System.IO.StreamWriter writer =new System.IO.StreamWriter(path,false))
{
    foreach (string[] line in Result)
    {
        writer.WriteLine(string.Join("\t", line)); 
    }
};