匹配花括号内的内容
Input: {abc}, Output: abc
正则表达式: (?<=\{)[^}]*(?=\})
(?<=\{) 匹配以左花括号开头
[^}]* 取得内容
(?=\}) 匹配以右花括号结束
private List<String> GetTokens(String str)
{
Regex regex = new Regex(@"(?<=\{)[^}]*(?=\})", RegexOptions.IgnoreCase);
MatchCollection matches = regex.Matches(str);
// Results include braces (undesirable)
return matches.Cast<Match>().Select(m => m.Value).Distinct().ToList();
}