C# 截取两个字符串中间的子字符串

/// <summary>
/// 截取中间字符
/// </summary>
/// <param name="text">全字符串</param>
/// <param name="start">开始字符串 </param>
/// <param name="end">结束字符串 </param>
/// <returns></returns>
public static string Substring(string text,string start,string end)
{
    Regex regex = new Regex("(?<=(" + start + "))[.\\s\\S]*?(?=(" + end + "))", RegexOptions.Multiline | RegexOptions.Singleline);
    return regex.Match(text).Value;
}