字符串问题，急
string   str= "this   is   a   book ";

例如以上字符串，怎么输出为 "book   a   is   this "

------解决方案--------------------
string str = "this is a book ";
string temp = " ";
foreach (string s in str.Split( ' '))
temp = " " + s + temp;
Text = temp.Remove(0, 1);