Comments by Faysel Kedir (Top 5 by date)

thanks for the help bro,but i just tried the steps you suggested and it ain't working !

currently my code is leting the user to insert same email address again and again

Dear i want to validate whether given email address exists or not in the database.

yes here is my sample code
SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["PaperShareConnectionString"].ConnectionString);
con.Open();

SqlCommand educmd = new SqlCommand("select higher_education from Users where Username='" + user.ToString() + "'",con);
educmd.CommandType = CommandType.Text;

SqlDataReader eduDr = educmd.ExecuteReader();
while (eduDr.Read())
{
higher_edu = eduDr["higher_education"].ToString();
Response.Write(higher_edu.ToString());
}
con.Close();

con.Open();
SqlCommand sqlCmd = new SqlCommand("select Username,first_name,last_name,sex from Users Where higher_education='"+higher_edu.ToString()+"'", con);
sqlCmd.CommandType = CommandType.Text;

SqlDataReader dr = sqlCmd.ExecuteReader();
while (dr.Read())
{
lblUsername.InnerText = dr["Username"].ToString();
lblFullname.InnerText= dr["first_name"].ToString() + dr["last_name"].ToString();
Response.Write(lblFullname.InnerText);
}

}