iOS, use string convert XML crash

[cxz137131304]

[cxz137131304]

DDXMLElement *message = [[DDXMLElement alloc] initWithXMLString:@"789489753824087e7b592ca-5d07-46f6-b0a7-ffd0f113c955Offline Storage" error:nil]; NSLog(@"%@", message);

this data is a right xml format, i can't found any wrong, please help！