Question

我有一些XML存储在数据库中，并作为字符串传递给我的方法。

<settings>
  <ReportOptions>
    <ReportWidget>
      <widget Name="Report Exclusions">
        <Visibility>
          <VisibilitySetting Name="ClosedLocations" Value="true"/>
        </Visibility>
      </widget>
      <widget Name="Report Period">
        <Visibility>
          <VisibilitySetting Name="Day" Value="true"/>
          <VisibilitySetting Name="Month" Value="true"/>
        </Visibility>
      </widget>
      <widget Name="Output Method">
        <Properties>
          <Visibility>
            <VisibilitySetting Name="Report Viewer" Value="true"/>
            <VisibilitySetting Name="Pdf" Value="true"/>
          </Visibility>
        </Properties>
      </widget>
    </ReportWidget>
  </ReportOptions>
</settings>

我在在线XPath测试器中运行以下表达式：

/settings/ReportOptions/ReportWidget/widget[@Name='Output Method']/Properties/Visibility/VisibilitySetting[@Name]

我得到以下结果：

<?xml version="1.0" encoding="UTF-8"?>
<result>
<VisibilitySetting Name="Report Viewer" Value="true"/>

<VisibilitySetting Name="Pdf" Value="true"/>

</result>

但是当我运行以下代码时：

var customizationApplied = false;
var firstProperty = Items[0];
var settings = firstProperty.Widget.Report.Settings;
var widgetName = firstProperty.Widget.Name;

// Select the node and place the results in an iterator
var strExpression =     settings.Compile("/settings/ReportOptions/ReportWidget/widget[@Name='Output Method']/Properties/Visibility/VisibilitySetting[@Name]");


var nodeIterator = settings.Select(strExpression);

// iterate through the results
while (nodeIterator.MoveNext())
{
    var xmlPropertyName = nodeIterator.Current.GetAttribute("Name", string.Empty);

    var propertyToCustomize = (from prop in Items
                               where string.Equals(prop.Name, xmlPropertyName, StringComparison.OrdinalIgnoreCase)
                               select prop).FirstOrDefault();

    if (propertyToCustomize != null)
    {
        var xmlPropertyValue = nodeIterator.Current.GetAttribute("Value", string.Empty);
        propertyToCustomize.IsEnabled = StringToObjectHelper.GetValue(xmlPropertyValue, false);

        customizationApplied = true;
    } 
}

我没有结果。 nodeIterator始终在鼠标悬停时显示：

Position=0, Current={Root}

当我执行nodeIterator.MoveNext（）方法时，它返回false。

有谁可以请问一下问题可能是什么？这一切都在以前工作，没有任何改变。

谢谢，利

Answer 1

为什么不使用标准.NET的LINQ-to-XML：

using System.Xml.XPath;
using System.Xml.Linq;

var xml = @"<settings>
  <ReportOptions>
    <ReportWidget>
      <widget Name=""Report Exclusions"">
        <Visibility>
          <VisibilitySetting Name=""ClosedLocations"" Value=""true""/>
        </Visibility>
      </widget>
      <widget Name=""Report Period"">
        <Visibility>
          <VisibilitySetting Name=""Day"" Value=""true""/>
          <VisibilitySetting Name=""Month"" Value=""true""/>
        </Visibility>
      </widget>
      <widget Name=""Output Method"">
        <Properties>
          <Visibility>
            <VisibilitySetting Name=""Report Viewer"" Value=""true""/>
            <VisibilitySetting Name=""Pdf"" Value=""true""/>
          </Visibility>
        </Properties>
      </widget>
    </ReportWidget>
  </ReportOptions>
</settings>";
var doc = XDocument.Parse(xml);
var nodes =
    doc.XPathSelectElements(
        "/settings/ReportOptions/ReportWidget/widget[@Name='Output Method']/Properties/Visibility/VisibilitySetting[@Name]");
foreach (var node in nodes)
{
    Console.WriteLine(node.ToString());
}

输出与在线XPath测试器的输出完全相同：

<VisibilitySetting Name="Report Viewer" Value="true"/>
<VisibilitySetting Name="Pdf" Value="true"/>

XPath没有找到节点

1 个答案: