c#:从这段这符"mp3\DJ音效\爱的勇气.mp3"中提取出:爱的勇气,代码如何写呢?

string str = @"mp3\DJ音效\爱的勇气.mp3";
int pos1 = str.LastIndexOf(@"\");
int pos2 = str.IndexOf(".");

string mp3Name = str.Substring(pos1 + 1, pos2 - pos1 - 1);

string strSentence = @"mp3\DJ音效\爱的勇气.mp3";//The goal string'
string[] strArr = strSentence.Split('\\'); //split by \,and saved to string[]
string strTemp = string.Empty; //save the goal
for (int i = 0; i <= strArr.Length - 1; i++)
{
if (strArr[i].Substring (0,5).Equals ("爱的勇气"))
{

strTemp = strArr[i].Substring (0,5);
}
}

string s = "mp3\DJ音效\爱的勇气.mp3";

int start = s.LastIndexOf(@"\");
int end = s.LastIndexOf(@".");

string s2 = s.SubString(start, end - start);

string path = @"mp3\DJ音效\爱的勇气.mp3";
pat