Why am I getting incorrect syntax near `username`? - asp.net

Question

public partial class adduser : System.Web.UI.Page
{
SqlConnection con = new SqlConnection(#"Data Source=(LocalDB)\v11.0;AttachDbFilename=|DataDirectory|\Database.mdf;Integrated Security=True");
SqlCommand cmd = new SqlCommand("insert into login values username = #un,password = #ps, sequirity_que = #sq, ans = #answer,usertype = #ustp ");
protected void Page_Load(object sender, EventArgs e)
{
}
protected void Button2_Click(object sender, EventArgs e)
{
cmd.Connection = con;
if (con.State != System.Data.ConnectionState.Open)
con.Open();
string un = txtusername.Text.Trim();
string ps = txtpass.Text.Trim();
string sq = txtseq.Text.Trim();
string answer = txtans.Text.Trim();
string ustp = DropDownList1.SelectedValue;
cmd.Parameters.Clear();
cmd.Parameters.AddWithValue("un", un);
cmd.Parameters.AddWithValue("ps", ps);
cmd.Parameters.AddWithValue("sq", sq);
cmd.Parameters.AddWithValue("answer", answer);
cmd.Parameters.AddWithValue("ustp", ustp);
//string qry = "insert into login values (username = '" + txtusername.Text + "',password='" + txtpass.Text + "',sequirity_que='" + txtseq.Text + "',ans='" + txtans.Text + "',usertype='" + DropDownList1.SelectedValue + "') ";
//SqlCommand md = new SqlCommand(qry,con);
int n= cmd.ExecuteNonQuery();
if(n>0)
{
Response.Write("User added");
}
else
{
Response.Write("fail");
}
}
}

Answer 1

This is the correct syntax of INSERT INTO:
SqlCommand cmd = new SqlCommand("insert into login (username, password, sequirity_que, ans, usertype) values (#un, #ps, #sq, #answer, #ustp)");
Some good examples