can anyone pls hlp me solve these errors?

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Text;
using System.IO;

namespace Default
{

protected void btnCreate_Click(object sender, EventArgs e)
{
string path = "D:\\MyTest.txt";
if (!File.Exists(path))
{
string() createText = { "Hello","Reading and writing text file" };
File.WriteAllLines(path, createText);
}
string appendText = "This is extra text" + Environment.NewLine;
File.AppendAllText(path, appendText);
lbltxt.Text = "File Created Successfully";
}
protected void btnRead_Click(object sender, EventArgs e)
{
string path = fileupload1.PostedFile.FileName;
if(!string.IsNullOrEmpty(path))
{
string() readText = File.ReadAllLines(path);
StringBuilder strbuild = new StringBuilder();
foreach (string s in readText)
{
strbuild.Append(s);
strbuild.AppendLine();
}
textBoxContents.Text = strbuild.ToString();
}