Helpful linqpad template for file manipulation

Template.cs

void Main()
{
	string fileName = ""; //Whatever the full path to the file in question is

	var lines = ReadLines(fileName);
		// Often I apply some filtering/modifying as follows:
		//.Skip(1) //If you need to skip some number of lines
                //.Split('\t') //Or ',', or whatever, but only if you want
                //.GroupBy(line => line[0]) //Again only if you want
	
	string.Join("\n", lines.Select(TransformLine)).Dump();
}

public static string TransformLine(string[] line)
{
	//Obviously you'll do something useful here.
	return string.Join(",", line);
}

public static IEnumerable<string> ReadLines(string source)
{
	using (var reader = new StreamReader(source))
	{
		string line;
		while ((line = reader.ReadLine()) != null)
		{
			yield return line;
		}
	}
}