C# 写入txt

//创建

FileStream fs = File.Create(@"D:/test.txt");

StreamWriter sw = new StreamWriter(fs);

sw.WriteLine("112233445566");

sw.Close();

fs.Close();

//读取

FileStream fss = File.OpenRead(@"D:/test.txt");

StreamReader sr = new StreamReader(fss);

string s = sr.ReadLine();

MessageBox.Show(s);

sr.Close();

fss.Close();

//增加

List<string> list = new List<string>();

list.Add("123456798");

File.AppendAllLines(@"D:/test.txt", list);

File.AppendAllText(@"D:/test.txt", "987654321");

StreamWriter swww= File.AppendText(@"D:/test.txt");

swww.WriteLine();

swww.WriteLine("555555");

swww.Close();

//sw追加

using (StreamWriter fs = new StreamWriter(path, true))

{

fs.WriteLine("");

}

读取 一行一行的读取

using (FileStream fs = new FileStream(@"D:/test.txt", FileMode.Open, FileAccess.Read))

{

StreamReader read = new StreamReader(fs, Encoding.Default);

string strReadline;

while ((strReadline = read.ReadLine()) != null)

{

//strReadline

}

}