我想用 C# 搜索大约一百个人类可读的缩进 XML 文件，使用 XPath 表达式，它应该返回每个找到的节点的文件名和行位置（以及列位置会很好），匹配 XPath .
我的目标是：将所有这些文件反序列化为一个对象树，其中包含几十个类，甚至程序中的更多实例。它的类有时是历史悠久的，需要进化/清理/重构。在更改之前我想检查更改的部分是否在任何地方使用，因为这些文件正在与不同的客户一起使用。稍后我将使用 XSLT 自动更改 XML 文件，同时改进代码。
奢侈的想法是构建一个用于在文件中搜索的 VS2010 插件——就像普通的“在文件中查找”对话框一样，但使用 XPath 作为搜索模式。
我发现 - 到目前为止 - 这里没有合适的东西，就像我的问题相反： 如何从 C# 中的行号和列号中找到 XML 节点？ 但作为输入，会有 XPath 表达式，而不是节点。
我以这种方式解决了它（以下代码的摘要）：
XPathDocumentCreateNavigatorSelect带有正则 XPath 表达式的方法XPathNavigator.MoveToPrevious() XPathNavigator.MoveToParent()//*[1]/*[10]/*[1]/*[3]，它标识与 found 相同的节点。这是快速编写的代码示例（方法搜索是入口点）：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Xml.XPath;
using System.Xml;
using System.IO;
using System.Diagnostics;
namespace XmlFileSearchMVP
{
public class XmlFileSearchModel : IXmlFileSearchModel
{
public XmlFileSearchModel()
{
}
/// <summary>
/// Search in all files (fitting the wildcard pattern in <paramref name="filter"/>) from the directory
/// <paramref name="path"/> for the XPath and report each found position in a string in the return value with
/// the informations:
/// + absolute file name path
/// + number of found occurrence
/// + line number
/// + column number
/// </summary>
/// <param name="path">file system path, containing the XML files, that have to be searched</param>
/// <param name="filter">file name with wildcards, e. g. "*.xml" or "*.mscx" or "*.gpx"</param>
/// <param name="xPath">XPath expression (currently only Xml Node resulting XPaths ok)</param>
/// <returns></returns>
public IList<string> Search(string path, string filter, string xPath)
{
string[] files = System.IO.Directory.GetFiles(path, filter);
var result = new List<string>();
for (int i = 0; i < files.Length; i++)
{
XPathDocument xpd = new XPathDocument(files[i]);
var xpn = xpd.CreateNavigator();
var xpni = xpn.Select(xPath);
int foundCounter = 0;
while (xpni.MoveNext())
{
foundCounter++;
var xn = xpni.Current;
var xnc = xn.Clone();
List<int> positions = new List<int>();
GetPositions(xn, ref positions);
string absXPath = GetAbsoluteXPath(positions);
// ok if xPath is looking for an element
var xpn2 = xpn.SelectSingleNode(absXPath);
bool samePosition = xnc.IsSamePosition(xpn2);
int y = -1;
int x = -1;
bool gotIt = GotFilePosition(files[i], positions, ref y, ref x);
result.Add(string.Format("{0} No. {1}: {2} {3} line {4}, col {5}", files[i], foundCounter, absXPath, gotIt, y, x));
}
result.Add(files[i] + " " + foundCounter.ToString());
}
return result;
}
/// <summary>
/// Evaluates the absolute position of the current node.
/// </summary>
/// <param name="node"></param>
/// <param name="positions">Lists the number of node in the according level, including root, that is first element. Positions start at 1.</param>
private static void GetPositions(XPathNavigator node, ref List<int> positions)
{
int pos = 1;
while (node.MoveToPrevious())
{
pos++;
}
if (node.MoveToParent())
{
positions.Insert(0, pos);
GetPositions(node, ref positions);
}
}
private static string GetAbsoluteXPath(List<int> positions)
{
StringBuilder sb = new StringBuilder("/", positions.Count * 5 + 1); // at least required...
foreach (var pos in positions)
{
sb.AppendFormat("/*[{0}]", pos);
}
return sb.ToString();
}
/// <summary>
/// base code from
/// http://msdn.microsoft.com/en-us/library/system.xml.ixmllineinfo%28v=vs.110%29
/// </summary>
/// <param name="xmlFile"></param>
/// <param name="positions"></param>
/// <param name="line"></param>
/// <param name="column"></param>
/// <returns></returns>
public static bool GotFilePosition(string xmlFile, List<int> positions, ref int line, ref int column)
{
// Create the XmlNamespaceManager.
XmlNamespaceManager nsmgr = new XmlNamespaceManager(new NameTable());
// Create the XmlParserContext.
XmlParserContext context = new XmlParserContext(null, nsmgr, null, XmlSpace.None);
// Create the reader.
using (FileStream fs = new FileStream(xmlFile, FileMode.Open, FileAccess.Read))
{
List<int> currPos = new List<int>();
XmlValidatingReader reader = new XmlValidatingReader(fs, XmlNodeType.Element, context);
try
{
IXmlLineInfo lineInfo = ((IXmlLineInfo)reader);
if (lineInfo.HasLineInfo())
{
// Parse the XML and display each node.
while (reader.Read())
{
switch (reader.NodeType)
{
case XmlNodeType.Document:
case XmlNodeType.Element:
Trace.Write(string.Format("{0} {1},{2} ", reader.Depth, lineInfo.LineNumber, lineInfo.LinePosition));
if (currPos.Count <= reader.Depth)
{
currPos.Add(1);
}
else
{
currPos[reader.Depth]++;
}
Trace.WriteLine(string.Format("<{0}> {1}", reader.Name, GetAbsoluteXPath(currPos)));
if (HasFound(currPos, positions))
{
line = lineInfo.LineNumber;
column = lineInfo.LinePosition;
return true;
}
break;
case XmlNodeType.Text:
Trace.Write(string.Format("{0} {1},{2} ", reader.Depth, lineInfo.LineNumber, lineInfo.LinePosition));
Trace.WriteLine(string.Format("{0} {1}", reader.Value, GetAbsoluteXPath(currPos)));
break;
case XmlNodeType.EndElement:
Trace.Write(string.Format("{0} {1},{2} ", reader.Depth, lineInfo.LineNumber, lineInfo.LinePosition));
while (reader.Depth < currPos.Count - 1)
{
currPos.RemoveAt(reader.Depth + 1); // currPos.Count - 1 would work too.
}
Trace.WriteLine(string.Format("</{0}> {1}", reader.Name, GetAbsoluteXPath(currPos)));
break;
case XmlNodeType.Whitespace:
case XmlNodeType.XmlDeclaration: // 1st read in XML document - hopefully
break;
case XmlNodeType.Attribute:
case XmlNodeType.CDATA:
case XmlNodeType.Comment:
case XmlNodeType.DocumentFragment:
case XmlNodeType.DocumentType:
case XmlNodeType.EndEntity:
case XmlNodeType.Entity:
case XmlNodeType.EntityReference:
case XmlNodeType.None:
case XmlNodeType.Notation:
case XmlNodeType.ProcessingInstruction:
case XmlNodeType.SignificantWhitespace:
break;
}
}
}
}
finally
{
reader.Close();
}
// Close the reader.
}
return false;
}
private static bool HasFound(List<int> currPos, List<int> positions)
{
if (currPos.Count < positions.Count)
{
return false; // tree is not yet so deep traversed, like the target node
}
for (int i = 0; i < positions.Count; i++)
{
if (currPos[i] != positions[i])
{
return false;
}
}
return true;
}
}
}
此示例应该可以帮助您入门：
using (StringReader stream = new StringReader(xml))
{
XPathDocument document = new XPathDocument(stream);
XPathNavigator navigator = document.CreateNavigator();
XPathExpression expression = navigator.Compile("/path/to/element");
XPathNodeIterator iterator = navigator.Select(expression);
try
{
while (iterator.MoveNext())
{
XPathNavigator current = iterator.Current;
string elementValue = current.Value;
IXmlLineInfo lineInfo = current as IXmlLineInfo;
if (lineInfo != null)
{
int lineNumber = lineInfo.LineNumber;
int linePosition = lineInfo.LinePosition;
}
}
}
catch
{
}
}