Question

我有这个LINQ查询。

var sumOfData = fullData.AsEnumerable().GroupBy(x => new { x.transactionId, x.checkId }).
        Where(p => (p.Key.checkId == variable.checkId) && (p.Key.transactionId == variable.transactionId))
        .Select(y => new
        {
                checkId = variable.checkId,
                transactionId = variable.transactionId,
                SumAppliedAmt = y.Sum(z => z.appliedAmount),
                SumCheckAmt = y.Sum(x => x.checkAmount)
        });

如何访问sumOfData内的数据？

访问sumOfData.checkId或sumOfData.transactionId需要执行哪些操作？我想在不使用foreach循环的情况下访问它。对不起，我忘了添加那部分。我已经使用foreach (var data in fullDataQuery)访问一个LINQ并将foreach置于foreach中将是性能密集型的{if（data.invoiceBalance ==）}

也可以直接更新到

var fullDataQuery = remitFile.AsEnumerable().Select(
                remitInfofullData => new
                    {
                        checkId = remitInfofullData.Field<int>("checkId"),
                        depositId = remitInfofullData.Field<int>("depositId"),
                        appliedAmount = remitInfofullData.Field<decimal>("appliedAmount"),
                        checkAmount = remitInfofullData.Field<decimal>("checkAmount"),
                        invoiceBalance = remitInfofullData.Field<decimal>("invoiceBalance"),
                        sequenceId = remitInfofullData.Field<int>("sequenceId"),
                        remittanceId = remitInfofullData.Field<int>("remittanceId"),
                        fileId = remitInfofullData.Field<int>("fileId"),
                        transactionId = remitInfofullData.Field<int>("transactionId"),

                    }).Where(p => (p.checkId == variable.checkId) && (p.transactionId == variable.transactionId)); using    var sumOfData = fullData.AsEnumerable().GroupBy(x => new { x.transactionId, x.checkId }).
    Where(p => (p.Key.checkId == variable.checkId) && (p.Key.transactionId == variable.transactionId))
    .Select(y => new
    {
            checkId = variable.checkId,
            transactionId = variable.transactionId,
            SumAppliedAmt = y.Sum(z => z.appliedAmount),
            SumCheckAmt = y.Sum(x => x.checkAmount)
    }); the sumAppliedAmount value

Answer 1

您可以像访问任何其他集合一样访问它。例如，您可以使用foreach：

来迭代项目

foreach (var item in sumOfData)
{
    //access properties on item by using item.checkId,
    //item.transactionId, item.SumAppliedAmt, item.SumCheckAmt
    //do your stuff
}

要在没有foreach 的情况下访问，您可以使用LINQ来执行检查金额最高的项目：

var highestCheckAmtItem = sumOfData.OrderByDescending(s => s.SumCheckAmt).First();

Answer 2

例如，您可以使用foreach枚举查询：

foreach (var x in sumOfData)
{
    var transactioID = x.transactionId;
    var checkId = x.checkId;
    var sumAppliedAmt = x.SumAppliedAmt;
    var sumCheckAmt = x.SumCheckAmt;
}

或您使用ToList创建List<YourAnonymousType>。但是，由于您只能在此方法中使用此匿名类型，因此如果要在不同位置使用它，则应使用真实类。

Answer 3

sumOfData是一个集合，而不是单个值。你可以这样做：

foreach (var element in sumOfData)
{
   Console.Write("CheckID is "+ element.checkId);
   Console.Write("transactionId  is "+ element.transactionId);
   Console.Write("SumAppliedAmt  is "+ element.SumAppliedAmt);
   Console.Write("SumCheckAmt  is "+ element.SumCheckAmt);
}

或者，您可以分别使用ToList()和ToArray将其转换为常规列表/数组。
另外，例如，如果您确定该集合只有一个元素（因为您正在过滤checkId / transactionId组合），您可以使用First或Single，如下所示：< / p>

var sumOfData = fullData
                .AsEnumerable()
                .GroupBy(...)
                .Where(...)
                .Select(...)
                .First();

将返回集合的第一个元素，不需要foreach，所以你可以做

Console.Write("CheckID is "+ sumOfData.checkId);
Console.Write("transactionId  is "+ sumOfData.transactionId);
Console.Write("SumAppliedAmt  is "+ sumOfData.SumAppliedAmt);
Console.Write("SumCheckAmt  is "+ sumOfData.SumCheckAmt);

如何从LINQ查询中获取匿名类型数据集的数据

3 个答案: