我在文档中有一个XElement.给定XElement(和XDocument？),是否有一个扩展方法来获取其完整(即绝对,例如/root/item/element/child)XPath？
例如myXElement.GetXPath()？
编辑:好的,看起来我忽略了一些非常重要的事情.哎呦!需要考虑元素的索引.请参阅我对修正后的解决方案的最后答案.
扩展方法:
public static class XExtensions
{
///
/// Get the absolute XPath to a given XElement
/// (e.g. "/people/person[6]/name[1]/last[1]").
///
public static string GetAbsoluteXPath(this XElement element)
{
if (element == null)
{
throw new ArgumentNullException("element");
}
Func relativeXPath = e =>
{
int index = e.IndexPosition();
string name = e.Name.LocalName;
// If the element is the root, no index is required
return (index == -1) ? "/" + name : string.Format
(
"/{0}[{1}]",
name,
index.ToString()
);
};
var ancestors = from e in element.Ancestors()
select relativeXPath(e);
return string.Concat(ancestors.Reverse().ToArray()) +
relativeXPath(element);
}
///
/// Get the index of the given XElement relative to its
/// siblings with identical names. If the given element is
/// the root, -1 is returned.
///
///
/// The element to get the index of.
///
public static int IndexPosition(this XElement element)
{
if (element == null)
{
throw new ArgumentNullException("element");
}
if (element.Parent == null)
{
return -1;
}
int i = 1; // Indexes for nodes start at 1, not 0
foreach (var sibling in element.Parent.Elements(element.Name))
{
if (sibling == element)
{
return i;
}
i++;
}
throw new InvalidOperationException
("element has been removed from its parent.");
}
}
而且测试:
class Program
{
static void Main(string[] args)
{
Program.Process(XDocument.Load(@"C:\test.xml").Root);
Console.Read();
}
static void Process(XElement element)
{
if (!element.HasElements)
{
Console.WriteLine(element.GetAbsoluteXPath());
}
else
{
foreach (XElement child in element.Elements())
{
Process(child);
}
}
}
}
和样本输出:
/tests/test[1]/date[1] /tests/test[1]/time[1]/start[1] /tests/test[1]/time[1]/end[1] /tests/test[1]/facility[1]/name[1] /tests/test[1]/facility[1]/website[1] /tests/test[1]/facility[1]/street[1] /tests/test[1]/facility[1]/state[1] /tests/test[1]/facility[1]/city[1] /tests/test[1]/facility[1]/zip[1] /tests/test[1]/facility[1]/phone[1] /tests/test[1]/info[1] /tests/test[2]/date[1] /tests/test[2]/time[1]/start[1] /tests/test[2]/time[1]/end[1] /tests/test[2]/facility[1]/name[1] /tests/test[2]/facility[1]/website[1] /tests/test[2]/facility[1]/street[1] /tests/test[2]/facility[1]/state[1] /tests/test[2]/facility[1]/city[1] /tests/test[2]/facility[1]/zip[1] /tests/test[2]/facility[1]/phone[1] /tests/test[2]/info[1]
那应该解决这个问题.没有？
我更新了Chris的代码,以考虑名称空间前缀.仅修改了GetAbsoluteXPath方法.
public static class XExtensions
{
///
/// Get the absolute XPath to a given XElement, including the namespace.
/// (e.g. "/a:people/b:person[6]/c:name[1]/d:last[1]").
///
public static string GetAbsoluteXPath(this XElement element)
{
if (element == null)
{
throw new ArgumentNullException("element");
}
Func relativeXPath = e =>
{
int index = e.IndexPosition();
var currentNamespace = e.Name.Namespace;
string name;
if (currentNamespace == null)
{
name = e.Name.LocalName;
}
else
{
string namespacePrefix = e.GetPrefixOfNamespace(currentNamespace);
name = namespacePrefix + ":" + e.Name.LocalName;
}
// If the element is the root, no index is required
return (index == -1) ? "/" + name : string.Format
(
"/{0}[{1}]",
name,
index.ToString()
);
};
var ancestors = from e in element.Ancestors()
select relativeXPath(e);
return string.Concat(ancestors.Reverse().ToArray()) +
relativeXPath(element);
}
///
/// Get the index of the given XElement relative to its
/// siblings with identical names. If the given element is
/// the root, -1 is returned.
///
///
/// The element to get the index of.
///
public static int IndexPosition(this XElement element)
{
if (element == null)
{
throw new ArgumentNullException("element");
}
if (element.Parent == null)
{
return -1;
}
int i = 1; // Indexes for nodes start at 1, not 0
foreach (var sibling in element.Parent.Elements(element.Name))
{
if (sibling == element)
{
return i;
}
i++;
}
throw new InvalidOperationException
("element has been removed from its parent.");
}
}
让我分享对这堂课的最新修改。基本上，如果element没有兄弟姐妹，它会排除索引，并且如果我遇到名称空间前缀问题，则使用local-name（）运算符包含名称空间。
public static class XExtensions
{
///
/// Get the absolute XPath to a given XElement, including the namespace.
/// (e.g. "/a:people/b:person[6]/c:name[1]/d:last[1]").
///
public static string GetAbsoluteXPath(this XElement element)
{
if (element == null)
{
throw new ArgumentNullException("element");
}
Func relativeXPath = e =>
{
int index = e.IndexPosition();
var currentNamespace = e.Name.Namespace;
string name;
if (String.IsNullOrEmpty(currentNamespace.ToString()))
{
name = e.Name.LocalName;
}
else
{
name = "*[local-name()='" + e.Name.LocalName + "']";
//string namespacePrefix = e.GetPrefixOfNamespace(currentNamespace);
//name = namespacePrefix + ":" + e.Name.LocalName;
}
// If the element is the root or has no sibling elements, no index is required
return ((index == -1) || (index == -2)) ? "/" + name : string.Format
(
"/{0}[{1}]",
name,
index.ToString()
);
};
var ancestors = from e in element.Ancestors()
select relativeXPath(e);
return string.Concat(ancestors.Reverse().ToArray()) +
relativeXPath(element);
}
///
/// Get the index of the given XElement relative to its
/// siblings with identical names. If the given element is
/// the root, -1 is returned or -2 if element has no sibling elements.
///
///
/// The element to get the index of.
///
public static int IndexPosition(this XElement element)
{
if (element == null)
{
throw new ArgumentNullException("element");
}
if (element.Parent == null)
{
// Element is root
return -1;
}
if (element.Parent.Elements(element.Name).Count() == 1)
{
// Element has no sibling elements
return -2;
}
int i = 1; // Indexes for nodes start at 1, not 0
foreach (var sibling in element.Parent.Elements(element.Name))
{
if (sibling == element)
{
return i;
}
i++;
}
throw new InvalidOperationException
("element has been removed from its parent.");
}
}
京公网安备 11010802040832号 | 京ICP备19059560号-6 
