public string deletePost(string forumName, string subForumName, int postNo, string requestingUser) { List <string> input = new List <string>() { forumName, subForumName, requestingUser }; if (Constants.isValidInput(input)) { lock (o) { postDeletionPermission pdp = _fm.getForumPostDeletionPermission(forumName); if (pdp == postDeletionPermission.INVALID) { return(Constants.noPermissionToDeletePost(requestingUser)); } permission p = _um.getUserPermissionsForSubForum(forumName, subForumName, requestingUser); if (p == permission.INVALID) { return(Constants.noPermissionToDeletePost(requestingUser)); } return(_fm.deletePost(forumName, subForumName, postNo, pdp, p, requestingUser)); } } return(Constants.INVALID_INPUT); }