如何通過多個家長XML文件c＃子元素

Question

我有一個XML文件中像這樣重複：

<post> 
    <categories> 
     <category ref="4527" /> 
     <category ref="4528" /> 
     <category ref="4529" /> 
     <category ref="4530" /> 
     <category ref="4531" /> 
    </categories> 
</post> 
<post> 
    <categories> 
     <category ref="4523" /> 
     <category ref="4524" /> 
     <category ref="4525" /> 
     <category ref="4526" /> 
     <category ref="4527" /> 
    </categories> 
</post> 

使用C＃和.NET 4.5我想要得到的第一組類別的參考數字，然後對其進行處理，然後移至下一組類別參考號碼並處理它們。我希望有人能指出我正確的方向。我不知道如何使用XPath或使用Linq到XML來完成此操作，或者如果這些都是正確的方法。提前致謝。

經過對一些非常聰明的人的一些迴應後，我能夠使用Selman22的思路幫助我編寫一些XPath。這裏是我想出瞭解決方案：

XmlDocument xdoc = new XmlDocument; 
xdoc.Load(savePath); 
XmlNode root = xdoc.DocumentElement; 
// add the namespace 
XmlNamespaceManager nsmgr = new XmlNamespaceManager(xdoc.NameTable); 
nsmgr.AddNamespace("bml", "http://www.blogml.com/2006/09/BlogML"); 
//puts the catagories elements into a list 
XmlNodeList blogCatagories = root.SelectNodes("descendant::bml:post/bml:categories", nsmgr); 
//loop throught list and place the attribute "ref" into a list and traverse each "ref" 
foreach (XmlNode nodeCat in blogCatagories) 
{ 
    XmlNodeList catagoryids = nodeCat.SelectNodes("descendant::bml:category/@ref", nsmgr); 
    foreach (XmlNode nodeID in catagoryids) 
    { 
     Console.WriteLine(nodeID.InnerText.ToString()); 

    } 
} 

Answer 1

首先通過類別列表讓你categories

var xdDoc = XDocument.Load(path); 
var categories = xDoc.Descendants("categories").ToList(); 

然後循環

foreach(var cat in categories) 
{ 
    var numbers = cat.Elements("category").Select(c => (int)c.Attribute("ref")); 

    foreach(var number in numbers) 
    { 
    // process your numbers 

    } 
} 

Answer 2

var xdoc = XDocument.Load(path_to_xml); 
var query = from p in xdoc.Root.Descendants("post") 
      select p.Element("categories") 
        .Elements("category") 
        .Select(c => (int)c.Attribute("ref")) 
        .ToList(); 

這個查詢將返回迭代器，這將讓每個你迭代它時類別參考號碼的下一個序列。

foreach(List<int> references in query) 
{ 
    // process list of references 
    foreach(int reference in references) 
     // process reference 
} 

Answer 3

我會使用的XPathDocument和XPathNavigator的，大量的實例對谷歌這樣

http://www.codegod.com/XPathDocument-XPathNavigator-XPathNodeIterator-sample-with-C-AID504.aspx

Answer 4

XPathNavigator xml = new XPathDocument(filename).CreateNavigator(); 
foreach(XPathNavigator categories in xml.Select("//categories")) 
{ 
    foreach(XPathNavigator category in categories.Select("category")) 
    { 
     string category_ref = category.GetAttribute("ref", string.Empty); 
    } 
    // do processing 
} 

Answer 5

經過對一些非常聰明的人的一些迴應後，我能夠使用Selman22的思路幫助我編寫一些XPath。

XmlDocument xdoc = new XmlDocument; 
xdoc.Load(savePath); 
XmlNode root = xdoc.DocumentElement; 
// add the namespace 
XmlNamespaceManager nsmgr = new XmlNamespaceManager(xdoc.NameTable); 
nsmgr.AddNamespace("bml", "http://www.blogml.com/2006/09/BlogML"); 
//puts the catagories elements into a list 
XmlNodeList blogCatagories = root.SelectNodes("descendant::bml:post/bml:categories", nsmgr); 
//loop throught list and place the attribute "ref" into a list and traverse each "ref" 
foreach (XmlNode nodeCat in blogCatagories) 
{ 
    XmlNodeList catagoryids = nodeCat.SelectNodes("descendant::bml:category/@ref", nsmgr); 
    foreach (XmlNode nodeID in catagoryids) 
    { 
     Console.WriteLine(nodeID.InnerText.ToString()); 

    } 
}