如何使用 xmlreader 获取第一个找到的节点的内容？

Question

如果我有这样的 xml 文件

<?xml version="1.0"?>
<?xml-stylesheet href="catalog.xsl" type="text/xsl"?>
<!DOCTYPE catalog SYSTEM "catalog.dtd">
<catalog>
   <product description="Cardigan Sweater" product_image="cardigan.jpg">
      <catalog_item gender="Men's">
         <item_number>QWZ5671</item_number>
         <price>39.95</price>
         <size description="Medium">
            <color_swatch image="red_cardigan.jpg">Red</color_swatch>
            <color_swatch image="burgundy_cardigan.jpg">Burgundy</color_swatch>
         </size>
         <size description="Large">
            <color_swatch image="red_cardigan.jpg">Red</color_swatch>
            <color_swatch image="burgundy_cardigan.jpg">Burgundy</color_swatch>
         </size>
      </catalog_item>
      <catalog_item gender="Women's">
         <item_number>RRX9856</item_number>
         <price>42.50</price>
         <size description="Small">
            <color_swatch image="red_cardigan.jpg">Red</color_swatch>
            <color_swatch image="navy_cardigan.jpg">Navy</color_swatch>
            <color_swatch image="burgundy_cardigan.jpg">Burgundy</color_swatch>
         </size>
         <size description="Medium">
            <color_swatch image="red_cardigan.jpg">Red</color_swatch>
            <color_swatch image="navy_cardigan.jpg">Navy</color_swatch>
            <color_swatch image="burgundy_cardigan.jpg">Burgundy</color_swatch>
            <color_swatch image="black_cardigan.jpg">Black</color_swatch>
         </size>
         <size description="Large">
            <color_swatch image="navy_cardigan.jpg">Navy</color_swatch>
            <color_swatch image="black_cardigan.jpg">Black</color_swatch>
         </size>
         <size description="Extra Large">
            <color_swatch image="burgundy_cardigan.jpg">Burgundy</color_swatch>
            <color_swatch image="black_cardigan.jpg">Black</color_swatch>
         </size>
      </catalog_item>
   </product>
</catalog>

如何使用 xmlreader 获取第一个 price 节点的值？ 我尝试了下面的代码，但它没有做我想要的......

XmlReaderSettings settings=new XmlReaderSettings();
settings.DtdProcessing=DtdProcessing.Ignore;
XmlReader reader=XmlReader.Create(@"D:\abc.xml",settings);
while (reader.Read())
{
    if ((reader.NodeType == XmlNodeType.Element) && (reader.Name=="price"))
    {
        Console.WriteLine(reader.ReadInnerXml().First());
    }
}

Console.ReadLine();

我在这里错过了什么？

我还听说 xmlreader 在读写大型 xml 文件方面比 Xdocument 好，如果我要减慢或崩溃我的程序需要多大在具有简单双核 cpu 和 1-2 GB 内存的 PC 上运行它？ 我想使用 foreach 循环读取和修改多个 xml 文件，并一一打开每个 xml 文件并执行读取/修改..

Answer 1

您的代码返回每个price 元素的第一个字符；您想返回所有第一个 price 元素然后停止。

while (reader.Read())
{
    if ((reader.NodeType == XmlNodeType.Element) && (reader.Name == "price"))
    {
        Console.WriteLine(reader.ReadInnerXml());
        break;
    }
}