inserting data from a textbox..

Heaven Valenzona

16y4.2k.NET

Hi.. I'm trying to insert data from a textbox. But there's an error..

here's my code:

 protected void Button1_Click(object sender, EventArgs e)
    {
        String insertSQL;
        insertSQL = "INSERT INTO SERVICES (";
        insertSQL += "Service_Code, Service_Name)";
        insertSQL += "VALUES (";
        insertSQL += "@Service_Code, @Service_Name)";



        String connectionstring = WebConfigurationManager.ConnectionStrings["HelpDesk_System"].ConnectionString;
        SqlConnection conn = new SqlConnection(connectionstring);
        SqlCommand cmd = new SqlCommand(insertSQL, conn);

        cmd.Parameters.AddWithValue("@Service_Code", TextBox1.Text);
        cmd.Parameters.AddWithValue("@Service_Name", TextBox2.Text);

         int added = 0;
        try
        {
            conn.Open();
            added = cmd.ExecuteNonQuery();
            UpdatePanel1.Update();
            conn.Close();


        }
        catch (Exception err)
        {
            Label1.Text = "Error inserting";
            Label2.Text += err.Message;
        }




    }
}

the error states that:

Object reference not set to an instance of an object.

What does it mean?

Thank you.

---ms SQL

---C#

---asp.net

7 Replies

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Dipa Ahuja16y ago
Accepted answer
m gal ... so dont call me sir :)

any ways the connection string that you have added in we.config file.. is that correct?

for ex:

retrive:

String connectionstring = ConfigurationManager.ConnectionStrings["ConnString"].ConnectionString;
Dipa Ahuja16y ago
Chirag is right..

the autonumber field does not allow you to insert data...

because its automatically generated..

Crish16y ago

hi

You can not insert value in Identity (primary key value where you have set autoincrement true) in table 'SERVICES'. So don't insert this ID value in this table. so it will work.

Don't forget to Mark Do you like this Answer
that solved your problem!

Heaven Valenzona16y ago
thank you!.. can I ask 1 more question? :)

may primary key service_code is a autonumber..

I get this error:
Error inserting
LabelCannot insert explicit value for identity column in table 'SERVICES' when IDENTITY_INSERT is set to OFF.

Why?
Dipa Ahuja16y ago
check the "name" of connection string i think thats y you r getting this erro:
Object reference not set to an instance of an object.
Heaven Valenzona16y ago
yes sir. I've already include that.. I use

String connectionstring = WebConfigurationManager.ConnectionStrings["HelpDesk_System"].ConnectionString;

then I use your suggested code.. but still no luck..

What do you mean by my connection string? is that the name of my database?
Dipa Ahuja16y ago
may be you are accessing wrong connection string Use the ConfigurationManager.ConnectionStrings

try this...

protected void Button1_Click(object sender, EventArgs e)
   {
   String insertSQL;
   insertSQL = "INSERT INTO SERVICES (Service_Code, Service_Name)VALUES (@Service_Code, @Service_Name)";

   String connectionstring = ConfigurationManager.ConnectionStrings["HelpDesk_System"].ConnectionString;

   SqlConnection conn = new SqlConnection(connectionstring);
   SqlCommand cmd = new SqlCommand(insertSQL, conn);
   cmd.Parameters.AddWithValue("@Service_Code", TextBox1.Text);
   cmd.Parameters.AddWithValue("@Service_Name", TextBox2.Text);

   int added = 0;
   try
   {
   conn.Open();
   added = cmd.ExecuteNonQuery();
   UpdatePanel1.Update();
   conn.Close();
   }
   catch (Exception err)
   {
   Label1.Text = "Error inserting"; Label2.Text += err.Message;
   }
   }