.NET-由于增量运算符或自动字符串转换,无法将代码从C转换为VB.NET(我认为)

我正在用vb.net编写一个库,在这个库中,我添加了一个最初用c语言编写但转换为vb.net的类。我对C不太了解,所以我使用了在线C到VB.NET转换器。现在我陷入了一些代码的困境,我相信在线转换器不能正确地“翻译”。

运行代码时,我得到以下错误:

System.IndexOutOfRangeException was unhandled
  Message="IndexOutOfRangeException"
  StackTrace:
    at System.String.get_Chars()
.........

我真的不明白这个错误的原因。我认为这个错误可能是由于以下两个原因之一: -C能够自动将整型变量转换为字符串(而VB.NET需要“ToString方法”)。 -或者由于C正在使用VB.NET不支持的增量运算符。

这里是C中的原始代码段,其中“m_primarykey”是一个StringBuilder对象:

private void addMetaphoneCharacter(String primaryCharacter, String alternateCharacter)
        {
            //Is the primary character valid?
            if (primaryCharacter.Length > 0)
            {
                int idx = 0;
                while (idx < primaryCharacter.Length)
                {
                    m_primaryKey.Length++;
                    m_primaryKey[m_primaryKeyLength++] = primaryCharacter[idx++];
                }
            }
            //other code deleted

当使用在C中创建的类库时,此原始代码可以工作。

下面是在vb.net中转换的代码,它给出了前面提到的错误:

Private Sub addMetaphoneCharacter(ByVal primaryCharacter As String, ByVal alternateCharacter As String)
            'Is the primary character valid? 
            If primaryCharacter.Length > 0 Then
                Dim idx As Integer = 0
                While idx < primaryCharacter.Length
                    m_primaryKey.Length += 1
                    m_primaryKey(System.Math.Max(System.Threading.Interlocked.Increment(m_primaryKeyLength), _
                        m_primaryKeyLength - 1)) = primaryCharacter _
                        (System.Math.Max(System.Threading.Interlocked.Increment(idx), idx - 1))
                End While
            End If 
           'other code deleted  

可以找到原始代码 here.

我应该说,课堂上的代码对我来说相当先进(我是一个业余程序员,但每天都在学习),所以也许我看不到明显的东西,但这就是我问你的原因。

你能给我一些提示来解决这个问题吗?

谢谢您。

编辑: 这是C中的完整子组件:

/**
         * Appends a metaphone character to the primary, and a possibly different alternate,
         * metaphone keys for the word.
         * 
         * @param primaryCharacter
         *               Primary character to append to primary key, and, if no alternate char is present,
         *               the alternate key as well
         * @param alternateCharacter
         *               Alternate character to append to alternate key.  May be null or a zero-length string,
         *               in which case the primary character will be appended to the alternate key instead
         */
        private void addMetaphoneCharacter(String primaryCharacter, String alternateCharacter)
        {
            //Is the primary character valid?
            if (primaryCharacter.Length > 0)
            {
                int idx = 0;
                while (idx < primaryCharacter.Length)
                {
                    m_primaryKey.Length++;
                    m_primaryKey[m_primaryKeyLength++] = primaryCharacter[idx++];
                }
            }

            //Is the alternate character valid?
            if (alternateCharacter != null)
            {
                //Alternate character was provided.  If it is not zero-length, append it, else
                //append the primary string as long as it wasn't zero length and isn't a space character
                if (alternateCharacter.Length > 0)
                {
                    m_hasAlternate = true;
                    if (alternateCharacter[0] != ' ')
                    {
                        int idx = 0;
                        while (idx < alternateCharacter.Length)
                        {
                            m_alternateKey.Length++;
                            m_alternateKey[m_alternateKeyLength++] = alternateCharacter[idx++];
                        }
                    }
                }
                else
                {
                    //No, but if the primary character is valid, add that instead
                    if (primaryCharacter.Length > 0 && (primaryCharacter[0] != ' '))
                    {
                        int idx = 0;
                        while (idx < primaryCharacter.Length)
                        {
                            m_alternateKey.Length++;
                            m_alternateKey[m_alternateKeyLength++] = primaryCharacter[idx++];
                        }
                    }
                }
            }
            else if (primaryCharacter.Length > 0)
            {
                //Else, no alternate character was passed, but a primary was, so append the primary character to the alternate key
                int idx = 0;
                while (idx < primaryCharacter.Length)
                {
                    m_alternateKey.Length++;
                    m_alternateKey[m_alternateKeyLength++] = primaryCharacter[idx++];
                }
            }
        }