ASI_POSTwithDict.m

NSDictionary *params = @{@"username": usernameInput,
                             @"password": passwordOutput,
                             @"uuid": deviceID,
                             @"device_name": [[UIDevice currentDevice] name],
                             @"version": [[[NSBundle mainBundle] infoDictionary] objectForKey:@"CFBundleShortVersionString"]};
    
    NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:@"%@/authentication_revised.php",host]];
    request = [ASIFormDataRequest requestWithURL:url];
    [request setRequestMethod:@"POST"];

    [params enumerateKeysAndObjectsUsingBlock:
     ^(id key, id value, BOOL *stop) {
         [request setPostValue:value forKey:key];
     }];