1

这是我的字符串值:

string str = "32 ab d32";

这个列表是我允许的字符:

var allowedCharacters = new List<string> { "a", "b", "c", "2", " " };

我希望它变成:

str == " 2 ab   2";

我想用空格替换不在允许字符列表中的任何字符。

4

5 回答 5

5

没有正则表达式:

IEnumerable<Char> allowed = srVariable
    .Select(c => lstAllowedCharacters.Contains(c.ToString()) ? c : ' ');
string result = new string(allowed.ToArray());
于 2012-12-11T16:48:16.327 回答
2

尝试这个:

string srVariable = "32 ab d32";
List<string> lstAllowedCharacters = new List<string> { "a", "b", "c", "2", " " };

srVariable = Regex.Replace(srVariable, "[^" + Regex.Escape(string.Join("", lstAllowedCharacters) + "]"), delegate(Match m)
{
    if (!m.Success) { return m.Value; }
    return " ";
});

Console.WriteLine(srVariable);
于 2012-12-11T16:49:07.890 回答
2

正则表达式?正则表达式对于您要完成的工作可能有点矫枉过正。

这是没有正则表达式的另一种变体(将您修改lstAllowedCharacters为实际上是可枚举的字符而不是字符串[正如变量名称所暗示的那样]):

String original = "32 ab d32";
Char replacementChar = ' ';
IEnumerable<Char> allowedChars = new[]{ 'a', 'b', 'c', '2', ' ' };

String result = new String(
  original.Select(x => !allowedChars.Contains(x) ? replacementChar : x).ToArray()
);
于 2012-12-11T16:51:38.573 回答
1

你为什么不使用String.Replace

于 2012-12-11T16:49:04.193 回答
1

这是一个简单但高效的 foreach 解决方案:

Hashset<char> lstAllowedCharacters = new Hashset<char>{'a','b','c','2',' '};

var resultStrBuilder = new StringBuilder(srVariable.Length);

foreach (char c in srVariable) 
{
    if (lstAllowedCharacters.Contains(c))
    {
        resultStrBuilder.Append(c);
    }
    else
    {
        resultStrBuilder.Append(" ");
    }
}

srVariable = resultStrBuilder.ToString();
于 2012-12-11T16:58:21.113 回答