private void ResetAll()
        {
            // Setzt Index der Combobox auf kein vorhandenes Element
            if (comboBoxID.SelectedIndex == -1)
            {
                // Leeren der Comcobox-Einträge
                comboBoxID.Items.Clear();
                // Leeren Eintrag einfügen, um alle Einträge zu erhalten
                comboBoxID.Items.Add("");
                // Alle in der DB gefunden IDs in der comboBoxID anzeigen
                comboBoxID.Items.AddRange(_logicSearch.ReadID(""));
                // ComboBoxID.Text auf das erste Element setzen
                if (comboBoxID.Items.Count > 0)
                {
                    comboBoxID.Text = comboBoxID.Items[0].ToString();
                }
            }

            // Auswahl Titel
            if (comboBoxTitle.SelectedIndex == -1)
            {
                comboBoxTitle.Items.Clear();
                comboBoxTitle.Items.Add("");
                comboBoxTitle.Items.AddRange(_logicSearch.ReadTitle(""));
                if (comboBoxTitle.Items.Count > 0)
                {
                    comboBoxTitle.Text = comboBoxTitle.Items[0].ToString();
                }
            }

            // Auswahl Genre
            if (comboBoxGenre.SelectedIndex == -1)
            {
                comboBoxGenre.Items.Clear();
                comboBoxGenre.Items.Add("");
                comboBoxGenre.Items.AddRange(_logicSearch.ReadGenre(""));
                if (comboBoxGenre.Items.Count > 0)
                {
                    comboBoxGenre.Text = comboBoxGenre.Items[0].ToString();
                }
            }

            // Auswahl Preis
            if (comboBoxBorrowingRate.SelectedIndex == -1)
            {
                comboBoxBorrowingRate.Items.Clear();
                comboBoxBorrowingRate.Items.Add("");
                comboBoxBorrowingRate.Items.AddRange(_logicSearch.ReadBorrowingRate(""));
                if (comboBoxBorrowingRate.Items.Count > 0)
                {
                    comboBoxBorrowingRate.Text = comboBoxBorrowingRate.Items[0].ToString();
                }
            }

            // Auswahl Erscheinungsjahr
            if (comboBoxReleaseYear.SelectedIndex == -1)
            {
                comboBoxReleaseYear.Items.Clear();
                comboBoxReleaseYear.Items.Add("");
                comboBoxReleaseYear.Items.AddRange(_logicSearch.ReadReleaseYear(""));
                if (comboBoxReleaseYear.Items.Count > 0)
                {
                    comboBoxReleaseYear.Text = comboBoxReleaseYear.Items[0].ToString();
                }
            }

            // Auswahl Laufzeit
            if (comboBoxRunningTime.SelectedIndex == -1)
            {
                comboBoxRunningTime.Items.Clear();
                comboBoxRunningTime.Items.Add("");
                comboBoxRunningTime.Items.AddRange(_logicSearch.ReadRunningTime(""));
                if (comboBoxRunningTime.Items.Count > 0)
                {
                    comboBoxRunningTime.Text = comboBoxRunningTime.Items[0].ToString();
                }
            }

            // Auswahl FSK
            if (comboBoxRated.SelectedIndex == -1)
            {
                comboBoxRated.Items.Clear();
                comboBoxRated.Items.Add("");
                comboBoxRated.Items.AddRange(_logicSearch.ReadRated(""));
                if (comboBoxRated.Items.Count > 0)
                {
                    comboBoxRated.Text = comboBoxRated.Items[0].ToString();
                }
            }

            // Auswahl Ausleihender
            if (comboBoxBorrower.SelectedIndex == -1)
            {
                comboBoxBorrower.Items.Clear();
                comboBoxBorrower.Items.Add("");
                comboBoxBorrower.Items.AddRange(_logicSearch.ReadBorrower(""));
                if (comboBoxBorrower.Items.Count > 0)
                {
                    comboBoxBorrower.Text = comboBoxBorrower.Items[0].ToString();
                }
            }

            // Auswahl Rückgabedatum
            if (comboBoxReturnDate.SelectedIndex == -1)
            {
                comboBoxReturnDate.Items.Clear();
                comboBoxReturnDate.Items.Add("");
                comboBoxReturnDate.Items.AddRange(_logicSearch.ReadReturnDate(""));
                if (comboBoxReturnDate.Items.Count > 0)
                {
                    comboBoxReturnDate.Text = comboBoxReturnDate.Items[0].ToString();
                }
            }
        }