Storing user data in a database

Question

How can I modify this code for writing user data to a text file so that it writes to a database.

private void button1_Click(object sender, EventArgs e)

{

string username = textBox1.Text;

string password = hash_password(textBox2.Text);

using (StreamWriter wr = System.IO.File.AppendText("C:\\pass.txt"))

{

wr.WriteLine(username + "," + password);

}

this.Close();

}

static string hash_password(string to_be_hashed)

{

byte[] arrbyte = new byte[to_be_hashed.Length];

SHA1 hash = new SHA1CryptoServiceProvider();

arrbyte = hash.ComputeHash(System.Text.Encoding.UTF8.GetBytes(to_be_hashed));

return Convert.ToBase64String(arrbyte);

}

 

And this code to read the data:

private void button1_Click(object sender, EventArgs e)

{

using (StreamReader reader = new StreamReader("C:\\pass.txt"))

{

string[] allLines = File.ReadAllLines(@"C:\pass.txt");

string[] usernames = new string[allLines.Length];

string[] passwords = new string[allLines.Length];

for (int i = 0; i < allLines.Length; i++)

{

string[] lineSplit = allLines[i].Split(',');

usernames[i] = lineSplit[0];

passwords[i] = lineSplit[1];

}

string username = textBox1.Text;

string password = hashed_password(textBox2.Text);

for (int i = 0; i < usernames.Length; i++)

if (usernames[i] == username)

if (passwords[i] == password)

{

this.Hide();

Form3 frm = new Form3();

frm.Show();

return;

}

else

{

MessageBox.Show("Incorrect username/password.");

return;

}

MessageBox.Show("Incorrect username/password.");

}

}

static string hashed_password(string to_be_hashed)

{

byte[] arrbyte = new byte[to_be_hashed.Length];

SHA1 hash = new SHA1CryptoServiceProvider();

arrbyte = hash.ComputeHash(System.Text.Encoding.UTF8.GetBytes(to_be_hashed));

return Convert.ToBase64String(arrbyte);

}

private void linkLabel1_LinkClicked(object sender, LinkLabelLinkClickedEventArgs e)

{

Form2 frm = new Form2();

frm.Show();

}

I'm really new to programming, and I can understand this code. If modifying this code is just not practical, could someone show me a simple (very simple) example of connecting to a database and storing data in it.