c# - 如何访问 linq 中等待方法的属性？

Question

我有这个查询，我找不到获取价格值的正确方法(.Amount.GetValueOrDefault())。

private IEnumerable<Product> GetSubsciptionOffers(IEnumerable<StripeProduct> productList)
{
    return productList
        .Select(async product => new Product
        {
            Name = product.Name,
            Id = product.Id,
            Image = new Uri(product.Images.First()),
            Description = product.Description,
            OfferType = OfferTypeEnum.Pro,
            Price = await _planRepo.GetPlanByIdAsync(product.Metadata.First().Value).Amount.GetValueOrDefault()
        });
}

错误是:

Task does not contain a definition for Amount

Answer 1

你必须用括号括起你的await:

Price = (await _planRepo.GetPlanByIdAsync(product.Metadata.First().Value)).Amount.GetValueOrDefault()

原因是 . 运算符比 await 运算符具有更高的优先级。