C#删除字符串中重复的字符
Func<string, string> RemoveDuplicate = delegate(string s) { BitArray _arr = new BitArray(256); StringBuilder _sb = new StringBuilder(); s = s.ToLower(); for (int i = 0; i < s.Length; i++) { if (_arr[(int)s[i]]) { continue; } else { _arr[(int)s[i]] = true; _sb.Append(s[i]); } } return _sb.ToString(); };