Check out example codes for "c# stringbuilder to file". It will help you in understanding the concepts better.

Code Example 1

using (System.IO.StreamWriter file = new System.IO.StreamWriter(@"\hereIam.txt"))
{
    file.WriteLine(sb.ToString()); // "sb" is the StringBuilder
}

Code Example 2

System.IO.File.WriteAllText(@"C:\TextFile.txt", stringBuilder.ToString());

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