c# - How add letter for the folders start -

i have folder , in folder have 50 folders. how can rename,it means, add letter of folder start,e.g., folder1 => afolder1?

i have tryed not work..

directoryinfo dir = new directoryinfo("c:/users/wiz/desktop/folder/"); foreach (var item in dir.getdirectories()) {     console.writeline("a" + item.name); } console.readline(); 

after adding soft should save new names in same directory...

as noted in comments: should move/rename folder, not print out name.

directoryinfo dir = new directoryinfo("c:/users/wiz/desktop/folder/"); foreach (var item in dir.getdirectories()) {     item.moveto(path.combine(item.parent.fullname, "a" + item.name));     console.writeline("a" + item.name);  }  console.readline();