How to read a text file reversely with iterator in C#

Question

I need to process a large file, around 400K lines and 200 M. But sometimes I have to process from bottom up. How can I use iterator (yield return) here? Basically I don\'t l

Answer 1

Very fast solution for huge files. Use powershell Get-Content cmdlet with Tail option. Calling powershell will give a little bit overhead, but for huge files its worthless

using System.Management.Automation;

const string FILE_PATH = @"d:\temp\b_media_27_34_0000_25393.txt";
var ps = PowerShell.Create();
ps.AddCommand("Get-Content")
    .AddParameter("Path", FILE_PATH)
    .AddParameter("Tail", 1);
var psResults = ps.Invoke();
var lastLine = psResults.FirstOrDefault()?.BaseObject.ToString();

ps.Dispose();

Required powershell reference

C:\Program Files (x86)\Reference Assemblies\Microsoft\WindowsPowerShell\3.0\System.Management.Automation.dll