第一单元11

static void Main(string[] args)
{
string s_text, s_key, s_result = null;
char ch;
int i;
Console.WriteLine("请输入原字符串：");
s_text = Console.ReadLine();
Console.WriteLine("请输入密钥字符串");
s_key = Console.ReadLine();
if (s_text.Length != s_key.Length)
{
Console.WriteLine("密钥字符串与原字符串长度必须相等");
}

else
{
for (i = 0; i < s_text.Length; i++)
{
ch = s_text[i];
s_result = s_result + (char)(ch - (s_key[i] - 48));
}
Console.WriteLine("加密后字符串为：");
Console.WriteLine(s_result);
}

Console.ReadLine();
}
}
}