我怎么能把这个换成任务。WhenAll()实现并行循环()?

我有下面的代码,检查跨域的用户组授权。代码使用各种域组合检查授权:

//build domain combos for lookup
var domainCombos = new List<Tuple<string, string>>();
domainCombos.Add(new Tuple<string, string>("corp-domain-1", "corp-domain-1"));
domainCombos.Add(new Tuple<string, string>("corp-domain-1", "corp-domain-2"));
domainCombos.Add(new Tuple<string, string>("corp-domain-2", "corp-domain-2"));
domainCombos.Add(new Tuple<string, string>("corp-domain-2", "corp-domain-1"));

var results = await Task.WhenAll(domainCombos.Select(domainCombo =>
{
    request.GroupDomainName = domainCombo.Item1;
    request.UserDomainName = domainCombo.Item2;
    return GetSingleAuthorizedGroupInfo(request);
}));
var aggregateResults = results.Where(x => x != null).SelectMany(result => result).ToList();
return aggregateResults;

我认为这是一个很好的候选人并行.ForEachb/c对GetSingleAuthorizedGroupInfo()的调用之间没有相互依赖关系。