batch commit rows to database in c# using a counter

Top off my mind here:

First option, do a quick count of '\n', thus getting the number of lines. Then, read chunks in multiple of 2 such that the result is very near to the number of lines, for example if 501 lines exist, read chunks of 250 and 250. Then only 1 line is left. When you first run the code, check for odd or even. If odd, remember to commit the last line, else if the number of lines are even, there is no need to compensate for the last line. Hope this helps.

P.S: After dividing the number into multiple of 2, if it is very large, you can further divide into 2 (Divide and conquer!)

If your read function returns false when there isn't anything else to read. then you can try this.

int i = 1;
while (read())
{
     if (i % 100 == 0)
     {
        for int (j = 0; j < 100; j++)
        { 
            write();
        }
     }
     i++;
}
for (int j = 0; j < i % 100; j++)
{
     write();
}

Something like this, perhaps? The following is pseudocode:

int rowCount = 0;
while more records to read
{
   // Get record
   // Parse record
   // Do something with results

   if(++rowCount % 100 == 0)
   {
      // Commit
      rowCount = 0;
   }
}
// If you have 0 records, you just did a commit (unless you had zero records to read,
// but I assume you can code your way around that!)  So you only need a final commit 
// if you had more than 0 records still uncommitted. 

if(rowCount > 0) 
{
   // Commit remaining records
}