//加载窗口
private void A_returnBook_Load(object sender, EventArgs e)
{
SqlConnection conn = SQLbase.getConn();
try
{
if (conn.State == ConnectionState.Open)
{
conn.Close();
}
conn.Open();
SqlCommand selectCmd = new SqlCommand("select * from returntable", conn);
SqlDataReader datareader = selectCmd.ExecuteReader();
string RID, BID, Bname;
int rowindex = 0;
this.datagridview.Rows.Clear();
while (datareader.Read())
{
RID = datareader["RID"].ToString();
Bname = datareader["Bname"].ToString();
BID = datareader["BID"].ToString();
rowindex = this.datagridview.Rows.Add();
//trim函数同于去除字符串两头的空格
this.datagridview.Rows[rowindex].Cells[0].Value = RID.Trim();
this.datagridview.Rows[rowindex].Cells[1].Value = BID.Trim();
this.datagridview.Rows[rowindex].Cells[2].Value = Bname.Trim();
}
}
catch
{
MessageBox.Show("操作错误！");
}
}
//查询按钮
private void button1_Click(object sender, EventArgs e)
{
SqlConnection conn = SQLbase.getConn();
try
{
this.datagridview.Rows.Clear(); //清空表格
//打开连接
if (conn.State == ConnectionState.Open)
{
conn.Close();
}
conn.Open();
string selectStr = "select * from Borrow";
//按读者号查询
if (comboBox_QueryStyle.SelectedIndex == 0)
{
string rid = txt_query.Text.ToString();
//建立查询命令
selectStr = "select * from Borrow where RID=" + rid;
}
//按书号查询
else if (comboBox_QueryStyle.SelectedIndex == 1)
{
string bid = txt_query.Text.ToString();
//建立查询命令
selectStr = "select * from Borrow where BID=" + bid;
}
//没有选择下拉框，则查询全部
SqlCommand selectCmd = new SqlCommand(selectStr, conn);
SqlDataReader datareader = selectCmd.ExecuteReader();
string BID, Bname, RID, Rname, BorrowDate, RealDate, Note;
int rowindex = 0;
this.datagridview.Rows.Clear();
while (datareader.Read())
{
RID = datareader["RID"].ToString();
BID = datareader["BID"].ToString();
BorrowDate = datareader["BorrowDate"].ToString();
RealDate = datareader["RealDate"].ToString();
Note = datareader["Note"].ToString();
rowindex = this.datagridview.Rows.Add();
//trim函数同于去除字符串两头的空格
this.datagridview.Rows[rowindex].Cells[0].Value = BID.Trim();
this.datagridview.Rows[rowindex].Cells[2].Value = RID.Trim();
this.datagridview.Rows[rowindex].Cells[4].Value = BorrowDate.Trim();
this.datagridview.Rows[rowindex].Cells[5].Value = RealDate.Trim();
this.datagridview.Rows[rowindex].Cells[6].Value = Note.Trim();
}
datareader.Close();
SQLbase.close(selectCmd);
int n = this.datagridview.RowCount;
for (int i = 0; i < n; i++)
{
//填充书名
BID = this.datagridview.Rows[i].Cells[0].Value.ToString();
Bname = selectBook(conn, BID);
this.datagridview.Rows[i].Cells[1].Value = Bname.Trim();
//填充作者名
RID = this.datagridview.Rows[i].Cells[2].Value.ToString();
Rname = selectReader(conn, RID);
this.datagridview.Rows[i].Cells[3].Value = Rname.Trim();
}
}
catch
{
MessageBox.Show("查无此记录！");
}
SQLbase.close(conn);
}