//取字符串长度
s = "iam方枪枪";
int len = s.Length;//will output as 6
byte[] sarr = System.Text.Encoding.Default.GetBytes(s);
len = sarr.Length;//will output as 3+3*2=9
//字符串相加
System.Text.StringBuilder sb = new System.Text.StringBuilder("");
sb.Append("i ");
sb.Append("am ");
sb.Append("方枪枪");