C#中如何将字符串转换byte[]，同时如何将byte[]换成字符串
1 string to byte []
string str = "abcd" ;
byte[] bytes = System.Text.Encoding.ASCII.GetBytes(str);
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2 byte[] to string
byte[] bytes = new byte[255] ;
string str = System.Text.Encoding.ASCII.GetString(bytes,0,bytes.Length);
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3. byte to string
byte a=4;
string str=a.toString();
