.net – 调用XmlReader :: ReadStartElement时抛出InvalidOperationException

我在C中编写了一个应用程序,它从类成员中生成 XML文件.现在我想再次读取生成的文件,并将所有属性和值保存回C类.

我的XML编写器(写成功)：

void TDescription::WriteXml( XmlWriter^ writer )
{
    writer->WriteStartElement( "Description" );
    writer->WriteAttributeString( "Version",m_sversion );
    writer->WriteAttributeString( "Author",m_sAuthor );
    writer->WriteString( m_sDescription );
    writer->WriteEndElement();
}

我的XML阅读器(导致异常)：

void TDescription::readxml( XmlReader^ reader )
{
    reader->ReadStartElement( "Description" );
    m_sversion = reader->GetAttribute( "Version" );
    m_sAuthor = reader->GetAttribute( "Author" );
    m_sDescription = reader->ReadString();
    reader->ReadEndElement();
}

我生成的XML文件：

<?xml version="1.0" encoding="utf-8"?>
<root Name="database" Purpose="try" Project="test">
     <!--Test Database-->
     <Description Version="1.1B" Author="it">primary</Description>
</root>

以下是读者引起的异常：

An unhandled exception of type 'system.invalidOperationException' occurred in System.Xml.dll

Additional information: There is an error in XML document (2,2).

代码有什么问题？我认为XmlReader方法没有以正确的方式使用！？

由于答案1,我更改了代码：

reader->ReadStartElement( "root" );
reader->ReadStartElement( "Description" );
m_sversion = reader->GetAttribute( "Version" );
m_sAuthor = reader->GetAttribute( "Author" );
m_sDescription = reader->ReadString();
reader->ReadEndElement();
reader->ReadEndElement();

现在,我没有得到异常,m_sDescription获取正确的值,但m_sversion和m_sAuthor仍为空.

解决方法

在此之前,您必须为“root”调用ReadStartElement.

reader->ReadStartElement( "root" );     
reader->ReadStartElement( "Description" );

编辑：读取属性

reader->ReadToFollowing( "Description" );
reader->MovetoFirstAttribute();
String ^ m_sversion = reader->Value;     
reader->MovetoNextAttribute();
String ^ m_sAuthor = reader->Value;           
String ^ m_sDescription = reader->ReadString();     
reader->ReadEndElement();