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Question

I am facing several errors in my code. These errors are:

• Error 17 The name 'CommandType' does not exist in the current context
• Error 18 The name 'SqlDbType' does not exist in the current context
• Error 35 The name 'txtCity' does not exist in the current context

I would like if you can help me to understand the error and tell me how I can fix it.

protected void btnSave_Click(object sender, EventArgs e)
{
    // create connectionstring and insert statment
    string connectionString = ConfigurationManager.ConnectionStrings["connectionString"].ConnectionString;
    string insertSql = " INSERT INTO UserInfo (UID, FN, LN, Password, RePass, Email, Country,State, City)" +
        " values (@UsrNme, @fnbox, @lnamebox, @passtxtbx1, @passtxtbx2, @emailbox, @DrDncoundrlst, @DropDownListSwestate, @citytxtbox)";

    // create SQL Connection

    SqlConnection con = new SqlConnection(connectionString);

    // create sql command and parameters

    SqlCommand cmd = new SqlCommand();
    cmd.Connection = con;
    cmd.CommandType = CommandType.text;
    cmd.CommandText = insertSql;

    SqlParameter UID = new SqlParameter("@UsrNme", SqlDbType.nvarchar, 50);
    UID.Value = txtUID.text.tostring();
    cmd.Parameters.Add(UID);

    SqlParameter FN = new SqlParameter("@fnbox", SqlDbType.varchar,25);
    cmd.Connection = con;
    FN.Value = txtfn.text.ToString();
    cmd.Parameters.Add(FN);



    SqlParameter LN = new SqlParameter("@lnamebox", SqlDbType.varchar, 25);
    cmd.Connection = con;
    LN.Value = txtLN.text.ToString();
    cmd.Parameters.Add(LN);

    SqlParameter Password = new SqlParameter("@passtxtbx1", SqlDbType.varchar, 25);
    cmd.Connection = con;
    Password.Value = txtPassword.text.ToString();
    cmd.Parameters.Add(Password);


    SqlParameter RePass = new SqlParameter("@passtxtbx2", SqlDbType.varchar, 25);
    cmd.Connection = con;
    RePass.Value = txtRePass.text.ToString();
    cmd.Parameters.Add(RePass);


    SqlParameter Email = new SqlParameter("@emailbox", SqlDbType.varchar, 25);
    cmd.Connection = con;
    Email.Value = txtEmail.text.ToString();
    cmd.Parameters.Add(Email);

    SqlParameter Country = new SqlParameter("@DrDncoundrlst", SqlDbType.varchar, 25);
    cmd.Connection = con;
    Country.Value = txtCountry.text.ToString();
    cmd.Parameters.Add(Country);

    SqlParameter State = new SqlParameter("@DropDownListSwestate", SqlDbType.varchar, 25);
    cmd.Connection = con;
    State.Value = txtState.text.ToString();
    cmd.Parameters.Add(State);

    SqlParameter City = new SqlParameter("@citytxtbox", SqlDbType.varchar, 25);
    cmd.Connection = con;
    City.Value = txtCity.text.ToString();
    cmd.Parameters.Add(City);

    try
    {
        con.Open();
        cmd.ExecuteNonQuery();
        lblmsg.Text = "You already complete your registration process";
    }
    catch (SqlException ex)
    {
        string errorMessage = "error in registration user";
        errorMessage += ex.Message;
        throw new Exception(errorMessage);
    }

    finally
    {
        con.Close();
    }

}

Answer 1

You may be way over-complicating things. Try the following code...

var connection = new SqlConnection(connectionString);
var cmd = new SqlCommand(insertSql, connection);

cmd.Parameters.AddWithValue("@UsrNme", txtUID.Text.ToString());
cmd.Parameters.AddWithValue("@fnbox", txtfn.Text.ToString());
cmd.Parameters.AddWithValue("@lnamebox", txtLN.Text.ToString());
cmd.Parameters.AddWithValue("@passtxtbx1", txtPassword.Text.ToString());
cmd.Parameters.AddWithValue("@passtxtbx1", txtPassword.Text.ToString());
cmd.Parameters.AddWithValue("@passtxtbx2", txtRePass.Text.ToString());
cmd.Parameters.AddWithValue("@emailbox", txtEmail.Text.ToString());
cmd.Parameters.AddWithValue("@DrDncoundrlst", txtCountry.Text.ToString());
cmd.Parameters.AddWithValue("@DropDownListSwestate", txtState.Text.ToString());
cmd.Parameters.AddWithValue("@citytxtbox", txtCity.Text.ToString());

try
{
    cmd.Connection.Open();
    cmd.ExecuteNonQuery();
    cmd.Connection.Close();

    lblmsg.Text = "You already completed your registration process";
}
catch (SqlException ex)
{
    var errorMessage = "error in registration user";

    errorMessage += ex.Message;

    throw new Exception(errorMessage);
}
finally
{
    con.Close();
}

You also want to make sure the you have the following using clauses declared...

using System.Data;
using System.Data.SqlClient;

... and that txtCity is what you actually called your text box and that it's not hidden from this method by a private identifier or actually appears on a different form because the error you're getting means that the variable is outside the method's scope or has its lifetime expire before you reach this method.

Here's what all that code does. Instead of setting up tons of metadata that you should not need to declare your parameters, it lets SqlCommand do all the hard work for you and figure out what type is what based on the database column, the type of the object you passed in, and the name of the parameter. If you end up allowing the passing of invalid data, none of the elaborate metadata markup is going to save you from an error.

Likewise, you really want to look into wrapping your insertSql into a stored procedure like so in Sql Server...

create procedure adduserinfo @UsrNme               nvarchar (50),
                             @fnbox                varchar (25),
                             @lnamebox             varchar (25),
                             @passtxtbx1           varchar (25),
                             @passtxtbx2           varchar (25),
                             @emailbox             varchar (25),
                             @DrDncoundrlst        varchar (25),
                             @DropDownListSwestate varchar (25),
                             @citytxtbox           varchar (25)

as begin
   INSERT INTO UserInfo 
     ( UID, 
       FN, 
       LN, 
       Password, 
       RePass, 
       Email, 
       Country,
       State, 
       City )
   VALUES
     ( @UsrNme, 
       @fnbox, 
       @lnamebox, 
       @passtxtbx1, 
       @passtxtbx2, 
       @emailbox, 
       @DrDncoundrlst, 
       @DropDownListSwestate, 
       @citytxtbox )
end
go

Then your SqlCommand declaration would look like so...

var command = new SqlCommand("adduserinfo", connection) 
{ 
    CommandType = CommandType.StoredProcedure; 
}

... and for the rest you'd follow the rest of the code I provided above. This would be the more or less proper way to do it. And at the risk of sounding nitpicky, consider more informative and consistently formatted variable and parameter names. Those who might have to modify your code in the future will thank you for it.