從字串中刪除指定的字元，如從字串this is an apple刪除aeiou字元

輸出:ths s n ppl

看到斑竹的部落格，覺得用正則更簡單些，特貼出來

/// <summary> /// 刪除字串中的指定字元 用正則，需要引用System.Text.RegularExpressions /// </summary> /// <param name="str">源字串</param> /// <param name="remove">要刪除的字元</param> /// <returns>處理後的字串</returns> public string RemoveChar(string str,string remove) { Regex r = new Regex(@"[" + remove + "]",RegexOptions.IgnoreCase); return r.Replace(str, ""); }

下面這是斑竹amandag用Dictionary寫的，感覺用法很活，放到這兒

static string RemoveChars(string str, string remove) { if(string.IsNullOrEmpty(str) || string.IsNullOrEmpty(remove)) { throw new ArgumentException("...."); } StringBuilder result = new StringBuilder(str.Length); Dictionary<char, bool> dictionary = new Dictionary<char, bool>(); foreach(char ch in remove) { dictionary[ch] = true; } foreach(char ch in str) { if(!dictionary.ContainsKey(ch)) { result.Append(ch); } } return result.ToString(); }