使用Linq-to-Xml和一些循环读取几个元素

本文关键字:几个 元素 读取 Linq-to-Xml 循环 使用 | 更新日期: 2023-09-27 18:15:13

使用以下代码,我目前正在读取每个<nv><ns>CounterSales</ns>(第三个元素),这很好。我将包括代码和XML。

这是代码,如果ElementAt是硬编码的,效果很好:

var xDoc = XDocument.Parse(xmlStr);
var nvs = xDoc.Descendants("nv");
var nads = nvs.Select(nv => nv.Elements("nad").First().Value).ToList();
var thirdRs = nvs.Select(nv => nv.Elements("r").ElementAt(2).Value).ToList();

xmlStr的值:

<ni>
    <nss>20150927</nss>
    <gp>Addon</gp>
    <ns>CounterBlah1</ns>
    <ns>CounterBlah2</ns>
    <ns>CounterSales</ns>
    <ns>CounterBlah4</ns>
    <ns>CounterBlah5</ns>
    <ns>CounterBlah6</ns>
    <nv>
        <nad>Style=1,Rfu=1,Id=132</nad>
        <r>0</r>
        <r>15</r>
        <r>8</r>
        <r>3</r>
        <r>2</r>
        <r>2</r>
    </nv>
    <nv>
        <nad>Style=1,Rfu=1,Id=433</nad>
        <r>0</r>
        <r>15</r>
        <r>30</r>
        <r>3</r>
        <r>2</r>
        <r>2</r>
    </nv>
    <nv>
        <nad>Style=1,Rfu=1,Id=665</nad>
        <r>0</r>
        <r>15</r>
        <r>90</r>
        <r>3</r>
        <r>2</r>
        <r>2</r>
    </nv>
</ni>

但是假设我想读取多个计数器。我有一个数据表,目前有两行:[CounterSales] &[CounterBlah5]。我想以同样的方式处理另外两个计数器:

int index = 0;
DataTable results = GetCounters();
//results has two rows: [CounterSales] & [CounterBlah5]
foreach (DataRow row in results.Rows)
{
    string counter = cellRow["counter"]; //counter equals "CounterSales"
    /* Iterate through all <ns> to see where "CounterSales" is located.
       In this case, index = 2. On next foreach, index equals 4  */
    var xDoc = XDocument.Parse(xmlStr);
    var nvs = xDoc.Descendants("nv");
    var nads = nvs.Select(nv => nv.Elements("nad").First().Value).ToList();
    var thirdRs = nvs.Select(nv => nv.Elements("r").ElementAt(index).Value).ToList();
}

任何帮助都是感激的。

谢谢。

使用Linq-to-Xml和一些循环读取几个元素

如果我正确理解了你的问题,这就是你需要的

DataTable results = GetCounters();
//results has two rows: [CounterSales] & [CounterBlah5]
foreach (DataRow row in results.Rows)
{
    string counter = cellRow["counter"]; //counter equals "CounterSales"
    /* Iterate through all <ns> to see where "CounterSales" is located.
        In this case, index = 2. On next foreach, index equals 4  */                
    var xDoc = XDocument.Parse(xmlStr);
    //here we find the index
    var requiredIndex = xDoc.Descendants("ns")
            .Select((node, idx) => new { node, idx})
            .First(x => x.node.Value.Equals(counter)).idx;
    var nvs = xDoc.Descendants("nv");
    var nads = nvs.Select(nv => nv.Elements("nad").First().Value).ToList();
    var thirdRs = nvs.Select(nv => nv.Elements("r").ElementAt(requiredIndex).Value).ToList();
}

编辑:从这篇文章中找到List<T>索引的更短语法。

var requiredIndex = xDoc.Descendants("ns").ToList().FindIndex(x => x.Value == counter);