0

这是一段给出异常FormatException的 Visual Basic 代码。

假设我的十六进制值 variablehexValue是 424E0A78。代码工作正常。当hexValue得到一个值（比如）424EA78时，就会发生这个异常：

提供的十六进制值为空或格式不正确。使用以下格式：00000000

有解决办法吗？

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
    Try
        Dim hexValue As String = "424E0A78"

        Dim iInputIndex As Integer = 0
        Dim iOutputIndex As Integer = 0
        Dim bArray(3) As Byte 'creating an array
        Dim rnum As Integer
        Dim rArray(3) As Byte
        Dim rSingle As Single
        Dim rSingle1 As Single
        Dim rSingle2 As Single
        Dim rStr As Integer
        Dim rnewArray(3) As Byte ' variables
        Dim rnum2, rnum3 As Integer 'variables
        Dim rstr2, rstr3 As String

        'For iInputIndex = 0 To hexValue.Length - 1 Step 2
        For iInputIndex = 0 To hexValue.Length - 1 Step 2

            'rnum3 = hexValue.Chars(iInputIndex) * 16

            'REjina code starts
            rStr = 0
            rstr2 = hexValue.Chars(iInputIndex)
            If (rstr2 = "A") Then
                rstr2 = 10
            ElseIf (rstr2 = "B") Then
                rstr2 = 11
            ElseIf (rstr2 = "C") Then
                rstr2 = 12
            ElseIf (rstr2 = "D") Then
                rstr2 = 13
            ElseIf (rstr2 = "E") Then
                rstr2 = 14
            ElseIf (rstr2 = "F") Then
                rstr2 = 15
            End If

            rStr = Val(rstr2) * 16

            'Second rejina conversion
            rstr2 = hexValue.Chars(iInputIndex + 1)
            If (rstr2 = "A") Then
                rstr2 = 10
            ElseIf (rstr2 = "B") Then
                rstr2 = 11
            ElseIf (rstr2 = "C") Then
                rstr2 = 12
            ElseIf (rstr2 = "D") Then
                rstr2 = 13
            ElseIf (rstr2 = "E") Then
                rstr2 = 14
            ElseIf (rstr2 = "F") Then
                rstr2 = 15
            End If

            rStr = rStr + Val(rstr2)

            'rstr2 = hexValue.Chars(iInputIndex + 1)
            rnewArray(iOutputIndex) = rStr
            'rejina code ends

            'rArray(iOutputIndex) = Byte.Parse(hexValue.Chars(iInputIndex) & hexValue.Chars(iInputIndex + 1), Globalization.NumberStyles.HexNumber)

            'bArray(iOutputIndex) = Convert.ToByte(hexValue.Chars(iInputIndex))

            iOutputIndex += 1
        Next

        'Array.Reverse(rArray)

        'rejina code starts
        Array.Reverse(rnewArray)
        'rejina code ends

        'Array.Reverse(bArray)


        'rSingle = BitConverter.ToSingle(rArray, 0)
        'rejina code starts
        rSingle1 = BitConverter.ToSingle(rnewArray, 0)
        'rejina code ends
        'rSingle2 = BitConverter.ToSingle(bArray, 0)

        MessageBox.Show(rSingle1)

        'Return BitConverter.ToSingle(rnewArray, 0)
    Catch ex As Exception
        Throw New FormatException("The supplied hex value is either empty or in an incorrect format. Use the following format: 00000000", ex)
    End Try
End Sub
4

1 回答 1

1

如果输入字符串的长度是奇数（即不是偶数），那么您将在该行上得到一个数组索引越界异常：

hexValue.Chars(iInputIndex + 1)

...这很可能是您在这里遇到的情况。

于 2012-11-24T08:28:26.897 回答