Разработка приложения для учета книг в библиотеке

                    dataGridView1.SelectedRows[0].Cells["Author"].Value = temp.Text;

                    dataGridView1.SelectedRows[0].Cells["Author"].Tag = 1;

                }

                else

                {

                    if (temp == textBoxGenre)

                    {

                        dataGridView1.SelectedRows[0].Cells["Genre"].Value = temp.Text;

                        dataGridView1.SelectedRows[0].Cells["Genre"].Tag = 1;

                    }

                    else

                    {

                        if (temp == textBoxName)

                        {

                            dataGridView1.SelectedRows[0].Cells["Book_Name"].Value = temp.Text;

                            dataGridView1.SelectedRows[0].Cells["Book_Name"].Tag = 1;

                        }

                        else

                        {

                            if (temp == textBoxPublishing)

                            {

                                dataGridView1.SelectedRows[0].Cells["Publishing"].Value = temp.Text;

                                dataGridView1.SelectedRows[0].Cells["Publishing"].Tag = 1;

                            }

                        }

                    }

                }

            }

        } 

        private void dataGridView1_RowEnter(object sender, DataGridViewCellEventArgs e)

        {

            if (dataGridView1.SelectedRows.Count != 0)

            {

                if (bEndBuild && dataGridView1.SelectedRows[0].Cells["Author"].Value.ToString() != "")

                {

                    textBoxPublishing.Text = dataGridView1.SelectedRows[0].Cells["Publishing"].Value.ToString();

                    textBoxName.Text = dataGridView1.SelectedRows[0].Cells["Book_Name"].Value.ToString();

                    textBoxGenre.Text = dataGridView1.SelectedRows[0].Cells["Genre"].Value.ToString();

                    textBoxAuthor.Text = dataGridView1.SelectedRows[0].Cells["Author"].Value.ToString();

                    if(dataGridView1.SelectedRows[0].Cells["Imprit_date"].Value.ToString() != "")

                        dateTimePickerImp.Value = (DateTime)dataGridView1.SelectedRows[0].Cells["Imprit_date"].Value;

                }

            }

        } 

        private void dateTimePickerImp_ValueChanged(object sender, EventArgs e)

        {

            if (dataGridView1.SelectedRows.Count != 0)

            {

                dataGridView1.SelectedRows[0].Cells["Imprit_date"].Value = dateTimePickerImp.Value.Year.ToString() + "-" +

                    dateTimePickerImp.Value.Month + "-" + dateTimePickerImp.Value.Day;

                dataGridView1.SelectedRows[0].Cells["Imprit_date"].Tag = 1;

            }

        } 

        private void button4_Click(object sender, EventArgs e)

        {

            dt.Rows.Add();

            dataGridView1["ID", dataGridView1.Rows.Count - 1].Tag = 1;

        } 

        private void button8_Click(object sender, EventArgs e)

        {

            for (int i = 0; i < dataGridView1.RowCount; i++)

            {

                if (dataGridView1["ID", i].Tag == null)

                {

                    for (int j = 1; j < dataGridView1.ColumnCount; j++)

                    {

                        if (dataGridView1[j, i].Tag != null)

                        {

                            if (dataGridView1.Columns[j].Name != "Imprit_date")

                            {

                                Util.UpdateGrid("Books", dataGridView1.Columns[j].Name,

                                                    dataGridView1[j, i].Value, dataGridView1["ID", i].Value.ToString());

                            }

                            else

                            {

                                DateTime temp = (DateTime)dataGridView1[j, i].Value;

                                Util.UpdateGrid("Books", dataGridView1.Columns[j].Name,

                                    temp.Year.ToString() + "-" + temp.Month + "-" + temp.Day,

                                    dataGridView1["ID", i].Value.ToString());

                            }

                        }

                    }

                }

                else

                {

                    Util.AddRow(dataGridView1.Rows[i], "Books");

                }

            }

        } 

        private void button6_Click(object sender, EventArgs e)

        {

            if (dataGridView1.SelectedRows.Count != 0)

            { 

                Util.DeleteRow(dataGridView1.SelectedRows[0], "Books");

                dt.Rows.RemoveAt(dataGridView1.SelectedRows[0].Index);

            }

        } 

        private void button5_Click(object sender, EventArgs e)

        {

    

        } 

        private void button1_Click_1(object sender, EventArgs e)

        {

            ForeignChoose form = new ForeignChoose("Shelf", SetShelf);

            form.Show();

        } 

        private void button7_Click(object sender, EventArgs e)

        { 

        } 

        private void checkBoxBook_CheckedChanged(object sender, EventArgs e)

        {

            bool checkBoxBook = true;

            if (dataGridView1.SelectedRows[0].Cells["Viewed"].Value != DBNull.Value)

            {

                if (Convert.ToBoolean(dataGridView1.SelectedRows[0].Cells["Viewed"].Value) == true)

                {

                    dataGridView1.SelectedRows[0].Cells["Viewed"].Value = false;

                    dataGridView1.SelectedRows[0].Cells["Viewed"].Tag = 1; 

                }

                else

                {

                    dataGridView1.SelectedRows[0].Cells["Viewed"].Value = true;

                    dataGridView1.SelectedRows[0].Cells["Viewed"].Tag = 1;

                }

            }

            else

            {

                dataGridView1.SelectedRows[0].Cells["Viewed"].Value = true;