Question

I have an ASP.Net website which is connected to an SQL Server. In a previous project (VB) I used the following code to write to my database:

Dim connectionString As String = ConfigurationManager.ConnectionStrings("DBConnection").ConnectionString
                Dim insertSql As String = "INSERT INTO tblProfile(UserID, UserName, Title, FirstName, LastName, MiddleName, DateofBirth, Gender, HomePhoneNumber, MobilePhoneNumber, Address, StreetName, StreetType, Suburb, PostCode, State, Country) VALUES(@UserID, @UserName, @Title, @FirstName, @LastName, @MiddleName, @DateofBirth, @Gender, @HomePhoneNumber, @MobilePhoneNumber, @Address, @StreetName, @StreetType, @Suburb, @PostCode, @State, @Country)"

                Using myConnection As New SqlConnection(connectionString)
                    myConnection.Open()
                    Dim myCommand As New SqlCommand(insertSql, myConnection)
                    myCommand.Parameters.AddWithValue("@UserID", newUserGuid)
                    myCommand.Parameters.AddWithValue("@UserName", newUserName)
                    myCommand.Parameters.AddWithValue("@Title", Title.SelectedItem.Text)
                    myCommand.Parameters.AddWithValue("@FirstName", FirstName.Text)
                    myCommand.Parameters.AddWithValue("@LastName", LastName.Text)
                    If MiddleNames.Text = String.Empty Then
                        myCommand.Parameters.AddWithValue("@MiddleName", DBNull.Value)
                    Else
                        myCommand.Parameters.AddWithValue("@MiddleName", MiddleNames.Text)
                    End If
                    DateofBirth.Text = YearofBirth.Text + "-" + MonthofBirth.Text + "-" + DayofBirth.Text
                    myCommand.Parameters.AddWithValue("@DateofBirth", DateofBirth.Text)
                    myCommand.Parameters.AddWithValue("@Gender", Gender.SelectedItem.Text)
                    If HomePhoneNumber.Text = String.Empty Then
                        myCommand.Parameters.AddWithValue("@HomePhoneNumber", DBNull.Value)
                    Else
                        myCommand.Parameters.AddWithValue("@HomePhoneNumber", HomePhoneNumber.Text)
                    End If
                    If MobilePhoneNumber.Text = String.Empty Then
                        myCommand.Parameters.AddWithValue("@MobilePhoneNumber", DBNull.Value)
                    Else
                        myCommand.Parameters.AddWithValue("@MobilePhoneNumber", MobilePhoneNumber.Text)
                    End If
                    myCommand.Parameters.AddWithValue("@Address", AddressNumber.Text)
                    myCommand.Parameters.AddWithValue("@StreetName", StreetName.Text)
                    myCommand.Parameters.AddWithValue("@StreetType", StreetType.SelectedItem.Text)
                    myCommand.Parameters.AddWithValue("@Suburb", Suburb.Text)
                    myCommand.Parameters.AddWithValue("@PostCode", Postcode.Text)
                    myCommand.Parameters.AddWithValue("@State", State.SelectedItem.Text)
                    myCommand.Parameters.AddWithValue("@Country", Country.SelectedItem.Text)

                    myCommand.ExecuteNonQuery()
                    myConnection.Close()
                End Using

I’ve now changed to C#, and am having problems altering this code. So far I have:

String connectionString = ConfigurationManager.ConnectionStrings["LocalSqlServer"].ConnectionString;

String insertSql = "INSERT INTO tbl_UserProfiles VALUES(@UserID, @FirstName, @LastName, @YearOfBirth, @Country)";
SqlCommand myCommand = new SqlCommand(insertSql, connectionString);
myCommand.Parameters.AddWithValue("@UserID", newUserGuid);
myCommand.Parameters.AddWithValue("@FirstName", FirstNameTB.Text);
myCommand.Parameters.AddWithValue("@LastName", LastNameTB.Text);
myCommand.Parameters.AddWithValue("@YearOfBirth", YearDDL.SelectedItem.Text);
myCommand.Parameters.AddWithValue("@Country", CountryDDL.SelectedItem.Text);

try
{
    connectionString.Open();
    myCommand.ExecuteNonQuery();
}

finally
{
    connectionString.Close();
}

Which I’ve tried to create after looking at a few tutorial sites and my own previous code. But, I believe I’m doing something wrong here:

String connectionString = ConfigurationManager.ConnectionStrings["LocalSqlServer"].ConnectionString;

as I get the squiggly red underline.

Answer 1

It looks like you are trying to Open() a connection string 🙂

Translate

  Using myConnection As New SqlConnection(connectionString)
                    myConnection.Open()
      Dim myCommand As New SqlCommand(insertSql, myConnection)

To

  using (var myConnection = new SqlConnection(connectionString))
  using (var myCommand = new SqlCommand(insertSql, myConnection))
  {
      myConnection.Open();
      ...
      myCommand.ExecuteNonQuery();
  }

using in C# on your SqlConnection and SqlCommand will guarantee that Dispose() is called on both objects, irrespective of whether success or fail (and close connections, cleanup etc)