图书借阅系统
遗失功能和Borrow表如图,
实现当输入Borrow中已有的借书证号bor_number和书号b_number时,修改Borrow里的loss。
当前代码可以执行但对表没用作用。但换成sqlstr = "update Borrow set loss='" & Trim(TextBox3.Text) & "'where bor_time='" & Trim(DateTimePicker1.Value) & "'and bac_time='" & Trim(DateTimePicker2.Value) & "'"就可以执行。我发现只要是另一个表的主键就无法实现,但是去掉主键无法实现功能。求助!!!
代码: Dim conn As SqlConnection
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Try
Me.Validate()
Me.BorrBindingSource1.EndEdit()
Me.BorrowTableAdapter.Update(Me.YSDataSet1.Borrow)
conn = New SqlConnection()
conn.ConnectionString = "Data Source=DESKTOP-0VDRKDC;Initial Catalog=student1;Integrated Security=True"
conn.Open()
Dim sqlstr As String
sqlstr = "update Borrow set loss='" & Trim(TextBox3.Text) & "'where bor_number='" & Trim(TextBox1.Text) & "' and b_number='" & Trim(TextBox2.Text) & "' and bor_time='" & Trim(DateTimePicker1.Value) & "'and bac_time='" & Trim(DateTimePicker2.Value) & "'"
Dim comm As New SqlCommand(sqlstr, conn)
comm.ExecuteNonQuery()
conn.Close()
MsgBox("添加信息成功")
Catch ex As Exception
MessageBox.Show(ex.Message)
End Try
End Sub