定义string变量为str,内存流变量为ms,比特数组为bt
1.字符串转比特数组
(1)byte[] bt=System.Text.Encoding.Default.GetBytes("字符串");
(2)byte[] bt=Convert.FromBase64String("字符串");
2.字符串转流
(1)MemoryStream ms=new MemoryStream(System.Text.Encoding.Default.GetBytes("字符串"));
(2)MemoryStream ms=new MemoryStream(Convert.FromBase64String("字符串"));
3.流转比特数组
(1)byte[] bt=ms.ToArray();
(2)MemoryStream ms=new MemoryStream();ms.Write(bt,0,ms.Length);
4.流转字符串
(1)string str=Convert.ToBase64String(ms.ToArray());
(2)string str=System.Text.Encoding.Default.GetString(ms.ToArray());
5.比特数组转字符串
(1)string str=System.Text.Encoding.Default.GetString(bt);
(2)string str=Convert.ToBase64String(bt);
6.比特数组转流
(1)MemoryStream ms=new MemoryStream(bt);
(2)MemoryStream ms=new MemoryStream();ms.Read(bt,0,bt.Length);
总结：可以看出byte[]在字符串string和流MemoryStream之间转换起到过渡的作用，string和MemoryStream转换都要先转换成byte[]。
