Question

我使用v s 2010 我有一个问题..当我使用datagridview的复选框从后端数据库删除多一行...当我删除连续多一行时，它在后端保持我的字段NO .... ...

但是假设当我删除第2行和第4行然后.......它无法维持后端..... 我的编程是* 当我删除一行然后所有的那一行得到的时候没有字段编号就像n = n-1 *

我的代码在这里......任何人都可以解决它......

Dim i, j, n As Integer
i = 0
j = 0
Dim x As Integer = 0
Dim a(1000) As String
a(x) = ""
Try
    While i < DataGridView1.Rows.Count
         If DataGridView1.Rows(i).Cells(0).Value() Then
              n = DataGridView1.Rows(i).Cells(1).Value()
              Call openconnection()
              'Here It Will Delete your Row From The Database Depending On Your Id....
              str = "DELETE FROM Assets_Detail Where   No=" & n & ""
              cmd = New SqlCommand(str, cn)
              cmd.ExecuteNonQuery()
              a(x) = n.ToString

              cn.Close()
              x = x + 1



         End If
         i = i + 1
    End While
Catch ex As Exception
    MsgBox(ex.ToString())
End Try
While j <= Val(a(x))
    Dim temp As Integer
    temp = Val(a(x))
    Call openconnection()
    str = "update Assets_Detail set No=No-1 where No > " & temp & ""
    cmd = New SqlCommand(str, cn)
    cmd.ExecuteNonQuery()
    cn.Close()

    j = j + 1
End While

Answer 1

简短的回答是，当您打算使用x和/或使用值而不是数组的长度时，我认为您正在使用j。换句话说，以下代码：

While j <= Val(a(x))
    Dim temp As Integer
    temp = Val(a(x))

应该是

While j <= a.Count()
    Dim temp As Integer
    temp = Val(a(j))

然而，更长的答案是我认为你的代码可能比它需要的更麻烦，并且需要更多的DB调用。一个示例是，当您可能应该使用While或For时，可以使用For Each。以下是建议的重构（但请注意，我不明白update Assets_Detail位应该如何工作，所以至少这一点可能是错误的）：

    Dim ids As New List(Of Integer)
    Try
        For Each row As DataRow In DataGridView1.Rows
            If row.Cells(0).Value() Then
                n = row.Cells(1).Value()                    
                ids.Add(CInt(n))
            End If
        Next

        Using cn As New SqlConnection("connectionstringhere")
            cn.Open()
            Dim Str As String = "DELETE FROM Assets_Detail Where No IN {0}"
            Using cmd As New SqlCommand(String.Format(Str, String.Join(", ", ids.ToArray())), cn)
                cmd.ExecuteNonQuery()
            End Using
        End Using

    Catch ex As Exception
        MsgBox(ex.ToString())
    End Try
    Try
        For Each id As Integer In ids
            Using cn As New SqlConnection("connectionstringhere")
                cn.Open()
                Dim str As String = "update Assets_Detail set No=No-1 where No > {0} "
                Using cmd As New SqlCommand(String.Format(str, id), cn)
                    cmd.ExecuteNonQuery()
                End Using
            End Using
        Next
    Catch ex As Exception
        MsgBox(ex.ToString())
    End Try

使用datagridview复选框删除多行的问题

1 个答案: