C＃在小int列中插入组合框项目索引

Question

I want to insert the selected item index from a combobox into a tinyint column ( FoodType ) in SQL Server. I wrote the code below, but I get an exception:

Must declare the scalar variable @fType

What must I do?

string query = "INSERT INTO MenuTbl (FoodName,FoodType,FoodUnit, SalePrice)" +
               "VALUES (@fName, @fType, @fUnit, @fPrice)";

connection = new SqlConnection(conectionString);

SqlCommand cmd = new SqlCommand(query,connection);
cmd.Parameters.AddWithValue("@fName", FNameTextBox.Text.Trim());
cmd.Parameters.AddWithValue("@fTyp", TypeComboBox.SelectedIndex + 1);
cmd.Parameters.AddWithValue("@funit", UnitComboBox.SelectedIndex +1);
cmd.Parameters.AddWithValue("@fprice", int.Parse(PriceEdit.Text));

connection.Open();
cmd.ExecuteNonQuery();
connection.Close();

Answer 1

I think you made a typo with this line of code

cmd.Parameters.AddWithValue("@fTyp", TypeComboBox.SelectedIndex + 1);

It should be @fType atleast according to your select query

 string query = "Insert into MenuTbl (FoodName,FoodType,FoodUnit, SalePrice)" +
         "VALUES (@fName,@fType,@fUnit, @fPrice)";

And I also think that TypeComboBox.SelectedIndex + 1 will only give you the index+1 numerical value rather than the selected text contents. Is that what you want?

Answer 2

您是否在参数上缺少“ e”？

cmd.Parameters.AddWithValue("@fTyp", TypeComboBox.SelectedIndex + 1);