What should be my connection string in this?

Question

I am trying to create page in asp.net page and I am getting the following error

Error:-System.NullReferenceException: Object reference not set to an instance of an object. at TestdateAssistor.user_info.Button1_Click1(Object sender, EventArgs e)

at this line-> SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["Data Source=LAPTOP-O9SI19I0\SQLEXPRESS;Integrated Security=True"].ConnectionString);

This is my complete code

       try
        {
            SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["Data Source=LAPTOP-O9SI19I0\\SQLEXPRESS;Integrated Security=True"].ConnectionString);
            conn.Open();
            String insert = "insert into Table (NAME,ADDRESS,MOBILE NO,ADHAR NO,DOB) values (@name,@add,@mob,@adhar,@dob)";
            SqlCommand com = new SqlCommand(insert,conn);
            com.Parameters.AddWithValue("@name",TextBox1.Text);
            com.Parameters.AddWithValue("@add",TextBox2.Text);
            com.Parameters.AddWithValue("@mob",TextBox3.Text);
            com.Parameters.AddWithValue("@adhar", TextBox4.Text);
            com.Parameters.AddWithValue("@dob", TextBox5.Text);
            com.ExecuteNonQuery();
            Response.Write("Successful Registration!!");
            conn.Close();
        }

        catch (Exception ex)
        {
            Response.Write("Error:-" + ex.ToString());
        }

What changes should I make?

You probably want to access the connection string by its name; how does the App/Web config look? — Sebastian Hofmann, Jun 17 '18 at 07:46
Please try and make question titles relevant to your question. — ProgrammingLlama, Jun 17 '18 at 07:51

score 1 · Answer 1 · answered Jun 17 '18 at 07:47

This line is incorrect:

SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["Data Source=LAPTOP-O9SI19I0\\SQLEXPRESS;Integrated Security=True"].ConnectionString);

It should be something like:

SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["datasourcename"].ConnectionString);

What should be my connection string in this?

1 Answers1