Question

我在下面的代码中收到OverflowException。

算术运算导致溢出。

Private Sub txtSearch_KeyPress(ByVal eventSender As System.Object, ByVal eventArgs As System.Windows.Forms.KeyPressEventArgs) Handles txtSearch.KeyPress
    Dim KeyAscii As Short = Asc(eventArgs.KeyChar)
    d = 0
    c = 0
    Dim strTitle As String
    Dim b As Short
    Dim length As Short
    length = Len(txtSearch.Text)

    If KeyAscii = 13 Then
        rf.MoveFirst()
        If txtSearch.Text = "" Then
            MsgBox("Search box empty.", MsgBoxStyle.Information)
            txtSearch.Focus()
        Else
            Do Until rf.EOF
                strTitle = rf.Fields("Title").Value
                For b = 1 To Len(strTitle) - length
                    If Mid(strTitle, b, length) = txtSearch.Text Then
                        d = d + 1
                        Exit For
                    End If
                Next
                rf.MoveNext()
            Loop
            lblTotal.Text = "" & d
            If d = 0 Then
                MsgBox("Keyword not found.", MsgBoxStyle.Critical)
                txtSearch.Text = ""
                txtSearch.Focus()
            Else
                rf.MoveFirst()
                Do Until rf.EOF
                    strTitle = rf.Fields("Title").Value
                    For b = 1 To Len(strTitle) - length
                        If Mid(strTitle, b, length) = txtSearch.Text Then
                            d = d + 1 '<-- Error occurs here.
                            Exit For
                        End If
                    Next
                Loop
            End If
        End If
    End If
    eventArgs.KeyChar = Chr(KeyAscii)
    If KeyAscii = 0 Then
        eventArgs.Handled = True
    End If
End Sub

Answer 1

无论d变量是什么数字类型，都是由于您尝试将其增加到比特定类型可能的值更大的值。

如果d是Short，则其最大值为32767.如果是Integer，则其最大值为2147483647.要么添加{{1} } -statements检查它是否即将溢出，或使用更大的数值数据类型（例如Long）。

通过查看If字段可以找到相应的最大值，例如Integer.MaxValue

如何修复此溢出异常未处理/算术运算导致溢出（d = d + 1部分代码）

1 个答案: