我该怎么修改啊

[一笔画冬]

Public Class Form1

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

        Str = TextBox1.Text
        Hst = Hex(Str)
        If Hst.Length < 5 Then

            Select Case Hst.Length
                Case Is = 1
                    zh = "000" + Hst
                Case Is = 2
                    zh = "00" + Hst
                Case Is = 3
                    zh = "0" + Hst
                Case Is = 4
                    zh = Hst
            End Select
            a = Mid(zh, 1, 2)
            b = Mid(zh, 3, 4)
            ' MsgBox(a)
            'MsgBox(b)
            Strz = "01 10 00 28 00 06 0C " & a & " " & b & " 00 00 D8 F0 FF FF " & c & " " & d
            MsgBox(Strz)
        End If


        Dim TempStr As String
        Dim i As Integer
        Dim LL As Long
        Dim Jyh0 As Byte
        Dim Jyh1 As Byte
        Dim ValCRC As Long

        c = ""
        d = ""
        If Trim(Strz) = "" Then Exit Sub '是空格，则跳出函数

        TempStr = ""
        For i = 1 To Len(Strz)
            TempStr = Mid(Trim(Strz), i, 1)
            If TempStr <> " " Then
                SendStr = SendStr + TempStr '去掉全部空格
            End If
        Next i

        LL = Len(SendStr)
        If (LL Mod 2) > 0 Then Exit Sub '奇数个字符，则跳出函数
        LL = LL / 2 - 1

        '重定义数组，下界为0
        For i = 0 To LL
            Cmd(i) = Val("&H" + Mid(SendStr, i * 2 + 1, 2) + "&") '！！！
        Next i

        ValCRC = CRC(Cmd)

        Jyh0 = ValCRC Mod 256
        Jyh1 = Int(ValCRC / 256) '取出CRC高低位

        c = Strings.Right("0" + Hex(Jyh0), 2)
        d = Strings.Right("0" + Hex(Jyh1), 2) 'Hex(10)，返回'A'

        RelayControl(Strz)

    End Sub



    Public Function CRC_part(ByVal Brr() As Byte) As Long ''''''CRC校验核，部分数据进行校验  Brr按地址传递！！！

        Dim i As Integer, j As Integer
        Dim TempVal As Long
        Dim YWval As Long
        Dim LSB As Integer

        TempVal = &HFFFF&

        For i = 0 To UBound(Brr()) - 2
            TempVal = TempVal Xor Brr(i)
            For j = 1 To 8
                YWval = Int(TempVal / 2)
                LSB = TempVal Mod 2
                If LSB = 1 Then
                    YWval = YWval Xor &HA001&
                End If
                TempVal = YWval
            Next j
        Next i
        CRC_part = TempVal Mod 65536

    End Function

    Private Sub TextBox1_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox1.KeyPress

        If Char.IsDigit(e.KeyChar) Or e.KeyChar = Chr(8) Or e.KeyChar = "." Then

            If e.KeyChar = "." And InStr(TextBox1.Text, ".") > 0 Then

                e.Handled = True

            Else

                e.Handled = False

            End If
        Else
            e.Handled = True

        End If
    End Sub

    '传入控制器模块指令
    Private Sub RelayControl(ByVal RelayInstruct As String)
        Try
            Dim SendArray() As String = Split(RelayInstruct)
            Dim HexBytes() As Byte
            ReDim HexBytes(SendArray.Length - 1)
            Dim i As Integer

            If SerialPort1.IsOpen Then
                SerialPort1.Close()
            End If
            SerialPort1.Open()

            For i = 0 To 16
                HexBytes(i) = Val("&H" & SendArray(i))
            Next
            SerialPort1.Write(HexBytes, 0, HexBytes.Length)

        Catch ex As Exception
    Public Function CRC(ByVal Brr() As Byte) As Long ''''CRC校验核，全部数据进行校验  Brr按地址传递！！！
        Dim i As Integer, j As Integer
        Dim TempVal As Long
        Dim YWval As Long
        Dim LSB As Integer

        TempVal = &HFFFF& '最后的&

        For i = 0 To UBound(Brr())
            TempVal = TempVal Xor Brr(i)
            For j = 1 To 8
                YWval = Int(TempVal / 2) 'Int，返回不大于x的最大整数
                LSB = TempVal Mod 2
                If LSB = 1 Then
                    YWval = YWval Xor &HA001& '?????
                End If
                TempVal = YWval
            Next j
        Next i
        CRC = TempVal Mod 65536

    End Function
        End Try

    End Sub

    Private Sub Label2_ParentChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Label2.ParentChanged
        Label2.Text = Strz
    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        RelayControl(Hstop)
    End Sub
End Class

写了一个程序，遍地错误
1：字符串到类型“long”的转换无效
2：索引数少于索引数组的维数。如图：

    Public Function CRC(ByVal Brr() As Byte) As Long ''''CRC校验核，全部数据进行校验  Brr按地址传递！！！
        For i = 0 To UBound(Brr()) 
    

[轻鸿万里]

字节型取元素到长整型要做格式转换