Select Query is not working

Question

Table Name:Index 

ID	Keyword
123,345,567	Test

 

I tried to get the ID values in a TextBox2 using following Code while entering the Keyword in TextBox1:

 

SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["Connection"].ToString()); 

 

protected void Button1_Click(object sender, EventArgs e)

{

SqlCommand cmd = new SqlCommand("select ID from Index where Keyword=@keyword",con);

cmd.Parameters.AddWithValue("@keyword",TextBox1.Text);

con.Open();

SqlDataReader dt = cmd.ExecuteReader();

if (dt.Read())

{

TextBox2.Text = dt.ToString();

}

 

But i got the result as

 

"System.Data.SqlClient.SqlDataReader"  in the TextBox2 ; what is the problem in my code???