ios 版本比较

#define currentVersion  [[NSBundle mainBundle] objectForInfoDictionaryKey:@"CFBundleShortVersionString"]

#pragma mark--判断版本号是不是大于本地版本
-(BOOL)compareVesionWithServerVersion:(NSString *)version{
    NSArray *versionArray = [version componentsSeparatedByString:@"."];//服务器返回版
    NSArray *currentVesionArray = [currentVersion componentsSeparatedByString:@"."];//当前版本
    NSInteger a = (versionArray.count> currentVesionArray.count)?currentVesionArray.count : versionArray.count;
    
    if ([version isEqualToString:currentVersion]) {
        return NO;
    }
    for (int i = 0; i< a; i++) {
        NSInteger a = [[versionArray objectAtIndex:i] integerValue];
        NSInteger b = [[currentVesionArray objectAtIndex:i] integerValue];
        if (a > b) {
            //            NSLog(@"有新版本");
            return YES;
        }else if(a < b){
            return NO;
        }
        
    }
    
    if (versionArray.count > currentVesionArray.count) {
        return YES;
    }
    if (versionArray.count < currentVesionArray.count ) {
        return NO;
    }
    
    return NO;
    
}