using?System;
using?System.Collections.Generic;
using?System.ComponentModel;
using?System.Data;
using?System.Data.SqlClient;
using?System.Drawing;
using?System.Linq;
using?System.Text;
using?System.Threading.Tasks;
using?System.Windows.Forms;
namespace?Database_Library
{
????public?partial?class?BooksFrom_admin?:?Form
????{
????????public?string?sql_default?=?“select?*?from?Books?where?ISBNum?=?‘-1‘“;
??
????????public?BooksFrom_admin（）
????????{
????????????InitializeComponent（）;
????????????ISBN_text.Text?=?““;
????????????bookname_text.Text?=?““;
????????????press_text.Text?=?““;
????????????writer_text.Text?=?““;
????????????totalnum_text.Text?=?“0“;
????????????numAvailable_text.Text?=?“0“;
????????????ifAvailable_combo.Text?=?““;
????????????update_btn.Enabled?=?false;
????????????delete_btn.Enabled?=?false;
????????????
????????}

????????private?void?readersbutton6_Click（object?sender?EventArgs?e）
????????{
????????????ReadersForm_admin?childrenForm_Readers?=?new?ReadersForm_admin（）;
????????????childrenForm_Readers.Show（）;
????????????this.Dispose（）;
????????}

????????private?void?deletebutton6_Click（object?sender?EventArgs?e）
????????{
??????????
????????????try
????????????{


????????????????int?index?=?selectresults.CurrentRow.Index;
????????????????string?isbnDstr?=?selectresults.Rows[index].Cells[0].Value.ToString（）.Trim（）;
????????????????string?deleteSql?=?String.Format（“delete?from?Books?where?ISBNum?=?‘{0}‘“?isbnDstr）;
????????????????string?confirmMess?=?String.Format（“確認(rèn)刪除圖書(shū){0}“?selectresults.Rows[index].Cells[1].Value.ToString（）.Trim（））;
????????????????if?（MessageBox.Show（confirmMess?“刪除確認(rèn)“?MessageBoxButtons.YesNo?MessageBoxIcon.Question?MessageBoxDefaultButton.Button1）?==?DialogResult.Yes）
????????????????{
????????????????????if?（DBoperations.ExecuteSql（deleteSql）?>?0）?//rows?>?0
????????????????????{
????????????????????????MessageBox.Show（“刪除成功“）;
????????????????????????selectresults.Rows.RemoveAt（index）;
????????????????????}
????????????????????else
????????????????????{
????????????????????????MessageBox.Show（“刪除失敗！“）;
????????????????????}
????????????????}
????????????}
????????????catch?（NullReferenceException?NotRefE）
????????????{
????????????????MessageBox.Show（“未選擇刪除對(duì)象！“）;
????????????????return;
????????????}
??????????
????????}

????????private?void?newaddbutton6_Click（object?sender?EventArgs?e）
????????{
????????????string?isbnStr?=?ISBN_text.Text.Trim（）;
????????????string?booknameStr?=?bookname_text.Text.Trim（）;
????????????string?pressStr?=?press_text.Text.Trim（）;
????????????string?writerStr?=?writer_text.Text.Trim（）;
????????????string?totalnumStr?=?totalnum_text.Text.Trim（）;
????????????string?avlblnumStr?=?numAvailable_text.Text.Trim（）;
????????????string?ifAvlblStr?=?ifAvailable_combo.Text.Trim（）;
????????????string?bookinsert?=?String.Format（“insert?into?Books?values?（‘{0}‘‘{1}‘‘{2}‘‘{3}‘{4}{5}‘{6}‘）“