c# How delete txt file 1st line?

Question

textbox4.Text already show .txt file 1st word.

Now I need how going delete 1st word from .txt file?

my code

    StreamReader objstream = new StreamReader("E:\\lastname.txt");

      textBox4.Text = objstream.ReadLine();

Answer 1

var lines = File.ReadAllLines("E:\\lastname.txt");
File.WriteAllLines("E:\\lastname.txt", lines.Skip(1).ToArray());

Answer 2

This question is a duplicate of: Removing the first line of a text file in C#.

Please someone close this.