HI I WAS BABIED MY ENTIRE LIFE

I'm pretty new to programming, and I've only worked with .NET thusfar. My friend wants me to hack some code into a C# game client. I extracted the source with Reflector and made the changes, but there is one unsafe bit I cannot get to compile, having never worked with C++ or any languages that use pointers:

        public static unsafe void Append(string value, ref uint crc)
        {
            if (m_Table == null)
            {
                m_Table = GenerateTable();
            }
            fixed (uint* numRef = m_Table)
            {
                fixed (char* str = ((char*) value))
                {
                    char* chPtr = str;
                    byte* numPtr = (byte*) chPtr;
                    byte* numPtr2 = numPtr + (value.Length * 2);
                    while (numPtr < numPtr2)
                    {
                        numPtr++;
                        uint index = (crc & 0xff) ^ numPtr[0];
                        crc = crc >> 8;
                        crc ^= numRef[index];
                    }
                }
            }
        }

I know it doesn't work because it's trying to cast a string to a char*, but I don't know how exactly to get this entire block working. I assume I need to convert the string into an array of char POINTERS (somehow :<) and go from there.

Can anyone help?

DON'T HELP HIM