/// <summary>
/// 查找一个byte数组在另一个byte数组第一次出现位置
/// </summary>
/// <param name="array">被查找的数组</param>
/// <param name="array2">要查找的数组</param>
/// <returns>找到返回索引，找不到返回-1</returns>
static int FindIndex(byte[] array, byte[] array2)
{
    int i, j;

    for (i = 0; i < array.Length; i++)
    {
        if (i + array2.Length <= array.Length)
        {
            for (j = 0; j < array2.Length; j++)
            {
                if (array[i + j] != array2[j]) break;
            }

            if (j == array2.Length) return i;
        }
        else
            break;
    }

    return -1;
}