基于C#实现XML文件读取工具类

本文实例讲述了基于c#实现xml文件读取工具类。分享给大家供大家参考。具体如下：

这是我去年写的一个xml文件读取工具类，现在做了一些调整
基本能满足一般的xml文件读取需求。
更新：
2013年6月26日19:37 fix了几个bug，为所有方法添加单元测试，并运行通过；同时调整了几个方法的位置。

/// <summary>
/// author: jiangxiaoqiang
/// </summary>
public class xmlreader
{
  //========================================================= //
  #region 获取xmldocument对象
  /// <summary>
  /// 根据xml文件内容获取xmldocument对象
  /// </summary>
  /// <param name="xmlfilecontent"></param>
  /// <returns></returns>
  public static xmldocument getxmldocbyxmlcontent(string xmlfilecontent)
  {
    if (string.isnullorempty(xmlfilecontent))
    {
      return null;
    }
    var xdoc = new xmldocument();
    try
    {
      xdoc.loadxml(xmlfilecontent);
    }
    catch
    {
      xdoc = null;
    }
    return xdoc;
  }
  /// <summary>
  /// 根据xml文件路径获取xmldocument对象
  /// </summary>
  /// <param name="xmlfilepath"></param>
  /// <returns></returns>
  public static xmldocument getxmldocbyfilepath(string xmlfilepath)
  {
    if (string.isnullorempty(xmlfilepath) || !file.exists(xmlfilepath))
    {
      return null;
    }
    var xdoc = new xmldocument();
    try
    {
      xdoc.load(xmlfilepath);
    }
    catch
    {
      throw new exception(string.format("请确认该xml文件格式正确，路径为：{0}", xmlfilepath));
    }
    return xdoc;
  }
  #endregion
  //========================================================= //
  //========================================================= //
  #region 获取xml节点（或节点列表）
  /// <summary>
  /// 获取父节点下指定节点名称的第一个子节点
  /// </summary>
  /// <param name="parentxmlnode"></param>
  /// <param name="childnodename"></param>
  /// <returns></returns>
  public static xmlnode getfirstchildnodebyname(xmlnode parentxmlnode, string childnodename)
  {
    var childxmlnodes = getchildnodesbyname(parentxmlnode, childnodename);
    if (childxmlnodes != null && childxmlnodes.count > 0)
    {
      return childxmlnodes[0];
    }
    return null;
  }
  /// <summary>
  /// 获取父节点下指定节点名称的子节点列表
  /// </summary>
  /// <param name="parentxmlnode">父节点</param>
  /// <param name="nodename">节点名称</param>
  /// <returns></returns>
  public static xmlnodelist getchildnodesbyname(xmlnode parentxmlnode, string nodename)
  {
    if (parentxmlnode == null || string.isnullorempty(nodename))
    {
      return null;
    }
    return getchildnodesbyxpathexpr(parentxmlnode, string.format(".//{0}", nodename));
  }
  /// <summary>
  /// 获取父节点下满足xpathexpr表达式的xml子节点列表
  /// </summary>
  /// <param name="parentxmlnode">父节点</param>
  /// <param name="xpathexpr"></param>
  /// <returns></returns>  
  public static xmlnodelist getchildnodesbyxpathexpr(xmlnode parentxmlnode, string xpathexpr)
  {
    if (parentxmlnode == null || string.isnullorempty(xpathexpr))
    {
      return null;
    }
    return parentxmlnode.selectnodes(xpathexpr);
  }
  /// <summary>
  /// 获取父节点下的第一个子节点
  /// </summary>
  /// <param name="parentxmlnode"></param>
  /// <returns></returns>
  public static xmlnode getfirstchildnode(xmlnode parentxmlnode)
  {
    var childxmlnodes = getchildnodes(parentxmlnode);
    if (childxmlnodes != null && childxmlnodes.count > 0)
    {
      return childxmlnodes[0];
    }
    return null;
  }
  /// <summary>
  /// 获取父节点的子节点列表
  /// </summary>
  /// <param name="parentxmlnode">父节点</param>
  /// <returns></returns>
  public static xmlnodelist getchildnodes(xmlnode parentxmlnode)
  {
    return parentxmlnode == null ? null : parentxmlnode.childnodes;
  }
  #endregion
  //========================================================= //
  //========================================================= //
  #region 读取节点属性值
  /// <summary>
  /// 读取某个xml节点的属性值（根据属性名）
  /// </summary>
  /// <param name="xmlnode"></param>
  /// <param name="attrname"></param>
  /// <returns></returns>
  public static string readattrvalue(xmlnode xmlnode, string attrname)
  {
    var xmlelement = xmlnode as xmlelement;
    return xmlelement == null ? null : xmlelement.getattribute(attrname);
  }
  /// <summary>
  /// 读取父节点下指定节点名和属性名的第一个子节点的属性值
  /// </summary>
  /// <param name="parentxmlnode">xml父节点</param>
  /// <param name="childnodename">节点名称</param>
  /// <param name="attrname">属性名</param>
  /// <returns></returns>
  public static string readfirstattrvalue(xmlnode parentxmlnode, string childnodename, string attrname)
  {
    var attrvals = readattrvalues(parentxmlnode, childnodename, attrname);
    return (attrvals == null || attrvals.length == 0) ? null : attrvals[0];
  }
  /// <summary>
  /// 读取父节点下指定节点名和属性名的所有子节点的该属性值的数组
  /// </summary>
  /// <param name="parentxmlnode">xml文档</param>
  /// <param name="childnodename">节点名称</param>
  /// <param name="attrname">属性名</param>
  /// <returns></returns>
  public static string[] readattrvalues(xmlnode parentxmlnode, string childnodename, string attrname)
  {
    if (parentxmlnode == null || string.isnullorempty(childnodename) || string.isnullorempty(attrname))
    {
      return null;
    }
    var xpathexpr = string.format("//{0}[@{1}]", childnodename, attrname);
    var nodes = getchildnodesbyxpathexpr(parentxmlnode, xpathexpr);
    if (nodes != null && nodes.count > 0)
    {
      var nodecount = nodes.count;
      var attrvals = new string[nodecount];
      for (var i = 0; i < nodecount; i++)
      {
        attrvals[i] = ((xmlelement)nodes[i]).getattribute(attrname);
      }
      return attrvals;
    }
    return null;
  }
  #endregion
  //========================================================= //
  //========================================================= //
  #region 读取父节点下的子节点的文本内容
  /// <summary>
  /// 读取父节点下指定节点名的第一个子节点的文本
  /// </summary>
  /// <param name="parentxmlnode"></param>
  /// <param name="childnodename"></param>
  /// <returns></returns>
  public static string readfirstchildnodetextbyname(xmlnode parentxmlnode, string childnodename)
  {
    var childnodetexts = readchildnodetextsbyname(parentxmlnode, childnodename);
    if (childnodetexts != null && childnodetexts.length > 0)
    {
      return childnodetexts[0];
    }
    return null;
  }
  /// <summary>
  /// 读取父节点下指定节点名的所有子节点的文本数组
  /// </summary>
  /// <param name="parentxmlnode"></param>
  /// <param name="childnodename"></param>
  /// <returns></returns>
  public static string[] readchildnodetextsbyname(xmlnode parentxmlnode, string childnodename)
  {
    if (parentxmlnode == null || string.isnullorempty(childnodename))
    {
      return null;
    }
    var xpathexpr = string.format(".//{0}", childnodename);
    var childnodes = getchildnodesbyxpathexpr(parentxmlnode, xpathexpr);
    if (childnodes != null && childnodes.count > 0)
    {
      var nodecount = childnodes.count;
      var nodetexts = new string[nodecount];
      for (var i = 0; i < nodecount; i++)
      {
        nodetexts[i] = childnodes[i].innertext;
      }
      return nodetexts;
    }
    return null;
  }
  /// <summary>
  /// 读取父节点下的第一个子节点的文本
  /// </summary>
  /// <param name="parentxmlnode"></param>
  /// <returns></returns>
  public static string readfirstchildnodetext(xmlnode parentxmlnode)
  {
    var childnodetexts = readchildnodetexts(parentxmlnode);
    if (childnodetexts != null && childnodetexts.length > 0)
    {
      return childnodetexts[0];
    }
    return null;
  }
  /// <summary>
  /// 读取父节点下的所有子节点的文本数组
  /// </summary>
  /// <param name="parentxmlnode"></param>
  /// <returns></returns>
  public static string[] readchildnodetexts(xmlnode parentxmlnode)
  {
    if (parentxmlnode == null)
    {
      return null;
    }
    var childnodes = getchildnodes(parentxmlnode);
    if (childnodes != null && childnodes.count > 0)
    {
      var nodecount = childnodes.count;
      var nodetexts = new string[nodecount];
      for (var i = 0; i < nodecount; i++)
      {
        nodetexts[i] = childnodes[i].innertext;
      }
      return nodetexts;
    }
    return null;
  }
  /// <summary>
  /// 读取xml节点文本
  /// </summary>
  /// <param name="xmlnode"></param>
  /// <returns></returns>
  public static string readnodetext(xmlnode xmlnode)
  {
    if (xmlnode == null)
    {
      return null;
    }
    return xmlnode.innertext;
  }
  #endregion
  //========================================================= //
}

希望本文所述对大家的c#程序设计有所帮助。