//Method to delete data from database public bool Delete(ContactClass cc) { //Creating a default return type and initializing it to false bool IsSuccess = false; //Step 1: Database Connection SqlConnection Conn = new SqlConnection(MyConnString); try { //Writing sql query string Sql = "DELETE FROM Contacts WHERE Contact_ID=@ContactID"; //Creating cmd using Sql and Conn SqlCommand SqlCmd = new SqlCommand(Sql, Conn); SqlCmd.Parameters.AddWithValue("@ContactID", cc.ContactID); //Opening Connection Conn.Open(); int Rows = SqlCmd.ExecuteNonQuery(); //if query runs successfully value of rows will be greater than 0 else less than 0 if (Rows > 0) { IsSuccess = true; } else { IsSuccess = false; } } catch (Exception ex) { MessageBox.Show(ex.Message, "Exception", MessageBoxButtons.OK, MessageBoxIcon.Error); } finally { //Closing connection Conn.Close(); } return(IsSuccess); }
//Method to update data in Database public bool Update(ContactClass cc) { //Creating a default return type and initializing it to false bool IsSuccess = false; //Step 1: Database Connection SqlConnection Conn = new SqlConnection(MyConnString); try { //Writing sql query string Sql = "UPDATE Contacts SET First_Name=@FirstName, Last_Name=@LastName, Email_Id=@EmailId, Contact_No=@ContactNo, Address=@Address, Gender=@Gender WHERE Contact_ID=@ContactID"; //Creating cmd using Sql and Conn SqlCommand SqlCmd = new SqlCommand(Sql, Conn); //Create Parameters to add data SqlCmd.Parameters.AddWithValue("@FirstName", cc.FirstName); SqlCmd.Parameters.AddWithValue("@LastName", cc.LastName); SqlCmd.Parameters.AddWithValue("@EmailId", cc.EmailId); SqlCmd.Parameters.AddWithValue("@ContactNo", cc.ContactNo); SqlCmd.Parameters.AddWithValue("@Address", cc.Address); SqlCmd.Parameters.AddWithValue("@Gender", cc.Gender); SqlCmd.Parameters.AddWithValue("@ContactID", cc.ContactID); //Opening Connection Conn.Open(); if (cc.FirstName == "" || cc.LastName == "" || cc.EmailId == "" || cc.ContactNo == "" || cc.Address == "" || cc.Gender == "") { MessageBox.Show("Please fill all the fields to add new contact", "Empty Fields Detected", MessageBoxButtons.OK, MessageBoxIcon.Warning); } else if (!ValidateEmail()) { MessageBox.Show("Enter a valid email address", "Invalid email address", MessageBoxButtons.OK, MessageBoxIcon.Error); } else { int Rows = SqlCmd.ExecuteNonQuery(); //if query runs successfully value of rows will be greater than 0 else less than 0 if (Rows > 0) { IsSuccess = true; } else { IsSuccess = false; } } } catch (Exception ex) { MessageBox.Show(ex.Message, "Exception", MessageBoxButtons.OK, MessageBoxIcon.Error); } finally { //Closing connection Conn.Close(); } return(IsSuccess); }