ios 版本比较

/* return: 有新版本返回YES */-(BOOL)compareOldVer:(NSString *)oldStr newVer:(NSString *)newStr{    NSMutableArray * oldAry =[NSMutableArray arrayWithArray: [oldStr componentsSeparatedByString:@"."]];    NSMutableArray * newAry =[NSMutableArray arrayWithArray:[newStr componentsSeparatedByString:@"."]];    if(oldAry.count>newAry.count){        while (newAry.count<oldAry.count) {            [newAry addObject:@"0"];        }    }else if(newAry.count > oldAry.count){        while (oldAry.count < newAry.count) {            [oldAry addObject:@"0"];        }    }        for(int i=0;i<newAry.count;i++){        int newVal = [[newAry objectAtIndex:i] intValue];        int oldVal = [[oldAry objectAtIndex:i] intValue];        if(newVal == oldVal){            continue;        }        if(newVal>oldVal){            return YES;        }else{            return NO;        }            }    return NO;}