如果有多個記錄，如何獲得具有相同id的多個記錄 <data> 來自xml的c＃中的元素

Question

如果存在多個數據元素，我想要多個記錄，因此對於每個數據記錄，id和log元素將保持相同。

注意：xml中會有多個元素，下面的例子中，下面只是單個元素

xml代碼：

<pay>
  <id>1</id>
  <data>
    <startDate>2016-03-03</startDate>
    <adjustedDueDate>2016-03-31</adjustedDueDate>
    <Rate>50</Rate>
</data>
<data>
    <startDate>2016-04-04</startDate>
    <adjustedDueDate>2016-04-04</adjustedDueDate>
    <Rate>12</Rate>
</data>
<log>IMP</log>
</pay>

C＃代碼

string path = @"E:\XMLFile1.xml";
XDocument xmlExeDoc = XDocument.Load(path);
var recordsFac = xmlExeDoc.Descendants("pay").Select(x => new
{
    id = (string)x.Element("id"),
    cycle = x.Elements("data").Select(y => new
    {
        startDate = (y.Elements("startDate").Any() == true) ? (string)y.Element("startDate") : string.Empty,
        adjustedDueDate = (DateTime)y.Element("adjustedDueDate"),
        Rate = (decimal)y.Element("Rate")
    }).Where(y => y.Rate > 0 && y.adjustedDueDate < DateTime.Now)
                           .Select
                           (
                               c => new
                               {
                                   startDate = c.startDate,
                                   adjustedDueDate = c.adjustedDueDate,
                                   Rate = c.Rate
                               }
                           ).FirstOrDefault(),

    log = x.Element("log")
}).ToList();

所需產量：

輸出：

[0] {1,2016-03-03,2016-03-31,50，IMP}

[1] {1,2016-04-04,2016-04-04,12，IMP}

需要相同的輸出像這里，但添加了另一個元素，我編碼如下給出是正確的方法，需要2行和2行元素。

<pay>
  <id>1</id>
  <data>
    <startDate>2016-03-03</startDate>
    <adjustedDueDate>2016-03-31</adjustedDueDate>
    <Rate>50</Rate>
</data>
<data>
    <startDate>2016-04-04</startDate>
    <adjustedDueDate>2016-04-04</adjustedDueDate>
    <Rate>12</Rate>
</data>
<log>IMP</log>
</pay>
<ClientData>
    <startDate>2016-07-04</startDate>
    <adjustedDueDate>2016-08-04</adjustedDueDate>
    <Rate>100</Rate>
</ClientData>
<ClientData>
    <startDate>2016-09-04</startDate>
    <adjustedDueDate>2016-09-04</adjustedDueDate>
    <Rate>555</Rate>
</ClientData>
</pay>



var recordsFac = xmlExeDoc.Descendants("pay").Select(x => new
{

    cycle = x.Elements("data").Select(y => new
    {
        id = (string)x.Element("id"),
        startDate = (y.Elements("startDate").Any() == true) ? (string)y.Element("startDate") : string.Empty,
        adjustedDueDate = (DateTime)y.Element("adjustedDueDate"),
        Rate = (decimal)y.Element("Rate"),
        log = x.Element("log")
    }).Where(y => y.Rate > 0 && y.adjustedDueDate < DateTime.Now),
    ClientData = x.Elements("data").Select(y => new
    {
        id = (string)x.Element("id"),
        startDate = (y.Elements("startDate").Any() == true) ? (string)y.Element("startDate") : string.Empty,
        adjustedDueDate = (DateTime)y.Element("adjustedDueDate"),
        Rate = (decimal)y.Element("Rate"),
        log = x.Element("log")
    }).Where(y => y.Rate > 0 && y.adjustedDueDate < DateTime.Now)

}).ToList();

上面的代碼是實現這個的正確方法：

輸出：

[0] {1,2016-03-03,2016-03-31,50，IMP}

[1] {1,2016-04-04,2016-04-04,12，IMP}

[2] {1,2016-07-04,2016-08-04,100，IMP}

[3] {1,2016-09-04,2016-09-04,555，IMP}

Answer 1

您的查詢已經產生了您要求的內容，但是您將循環查詢限制為FirstOrDefault，因此它只會產生1條記錄。 如果刪除它，則循環包含兩個記錄。

要獲取id並記錄與日期相同的記錄，只需將它們包含在您正在創建的最終匿名類中：

var recordsFac = xmlExeDoc.Descendants("pay").Select(x => new
{

    cycle = x.Elements("data").Select(y => new
    {
        startDate = (y.Elements("startDate").Any() == true) ? (string)y.Element("startDate") : string.Empty,
        adjustedDueDate = (DateTime)y.Element("adjustedDueDate"),
        Rate = (decimal)y.Element("Rate"),
    }).Where(y => y.Rate > 0 && y.adjustedDueDate < DateTime.Now)
                           .Select
                           (
                               c => new
                               {
                                   id = (string)x.Element("id"),
                                   startDate = c.startDate,
                                   adjustedDueDate = c.adjustedDueDate,
                                   Rate = c.Rate,
                                   log = x.Element("log")
                               }
                           ),

}).ToList();

recordsFac將包含xml文件中每個pay元素的記錄。 每條記錄的循環屬性將包含您概述的數據。 一個簡單的嵌套foreach循環將訪問數據：

foreach(var record in recordsFac)
{
    foreach(var record2 in record.cycle)
    {
        Console.WriteLine($"{record2.id},{record2.startDate},{record2.adjustedDueDate},{record2.log}");
    }
}

再看看你的代碼，注意到最后一個選擇是多余的，可以刪除：

var recordsFac = xmlExeDoc.Descendants("pay").Select(x => new
{

    cycle = x.Elements("data").Select(y => new
    {
        id = (string)x.Element("id"),
        startDate = (y.Elements("startDate").Any() == true) ? (string)y.Element("startDate") : string.Empty,
        adjustedDueDate = (DateTime)y.Element("adjustedDueDate"),
        Rate = (decimal)y.Element("Rate"),
        log = x.Element("log")
    }).Where(y => y.Rate > 0 && y.adjustedDueDate < DateTime.Now)               
}).ToList();

foreach(var record in recordsFac)
{
    foreach(var record2 in record.cycle)
    {
        Console.WriteLine($"{record2.id},{record2.startDate},{record2.adjustedDueDate},{record2.log}");
    }
}