我想到了..
public void SetFileSecurity(String filePath, String domainName, String userName)
{
//get file info
FileInfo fi = new FileInfo(filePath);
//get security access
FileSecurity fs = fi.GetAccessControl();
//remove any inherited access
fs.SetAccessRuleProtection(true, false);
//get any special user access
AuthorizationRuleCollection rules = fs.GetAccessRules(true, true, typeof(System.Security.Principal.NTAccount));
//remove any special access
foreach (FileSystemAccessRule rule in rules)
fs.RemoveAccessRule(rule);
//add current user with full control.
fs.AddAccessRule(new FileSystemAccessRule(domainName + "\\" + userName, FileSystemRights.FullControl, AccessControlType.Allow));
//add all other users delete only permissions.
fs.AddAccessRule(new FileSystemAccessRule("Authenticated Users", FileSystemRights.Delete, AccessControlType.Allow));
//flush security access.
File.SetAccessControl(filePath, fs);
}