将 XML 读入列表对象

问题描述

我很难将 XML 文件读入 vb.net 中的 List(Of Object) 任何帮助将不胜感激。

反序列化时出现问题。我收到以下错误

system.invalidOperationException: 'XML 文档 (2,2) 中存在错误。'

内部异常 InvalidOperationException: 不是预期的。

XML

<?xml version="1.0" encoding="UTF-8"?>
<CRecord>
  <CD>
    <TITLE>Empire Burlesque</TITLE>
    <ARTIST>Bob Dylan</ARTIST>
    <COUNTRY>USA</COUNTRY>
    <COMPANY>Columbia</COMPANY>
    <PRICE>10.90</PRICE>
    <YEAR>1985</YEAR>
  </CD>
  <CD>
    <TITLE>Hide your heart</TITLE>
    <ARTIST>Bonnie Tyler</ARTIST>
    <COUNTRY>UK</COUNTRY>
    <COMPANY>CBS Records</COMPANY>
    <PRICE>9.90</PRICE>
    <YEAR>1988</YEAR>
  </CD>
  <CD>
    <TITLE>Greatest Hits</TITLE>
    <ARTIST>Dolly Parton</ARTIST>
    <COUNTRY>USA</COUNTRY>
    <COMPANY>RCA</COMPANY>
    <PRICE>9.90</PRICE>
    <YEAR>1982</YEAR>
  </CD>
  <CD>
    <TITLE>Still got the blues</TITLE>
    <ARTIST>Gary Moore</ARTIST>
    <COUNTRY>UK</COUNTRY>
    <COMPANY>Virgin records</COMPANY>
    <PRICE>10.20</PRICE>
    <YEAR>1990</YEAR>
  </CD>
  <CD>
    <TITLE>Eros</TITLE>
    <ARTIST>Eros Ramazzotti</ARTIST>
    <COUNTRY>EU</COUNTRY>
    <COMPANY>BMG</COMPANY>
    <PRICE>9.90</PRICE>
    <YEAR>1997</YEAR>
  </CD>
  <CD>
    <TITLE>One night only</TITLE>
    <ARTIST>Bee Gees</ARTIST>
    <COUNTRY>UK</COUNTRY>
    <COMPANY>polydor</COMPANY>
    <PRICE>10.90</PRICE>
    <YEAR>1998</YEAR>
  </CD>
  <CD>
    <TITLE>Sylvias Mother</TITLE>
    <ARTIST>Dr.Hook</ARTIST>
    <COUNTRY>UK</COUNTRY>
    <COMPANY>CBS</COMPANY>
    <PRICE>8.10</PRICE>
    <YEAR>1973</YEAR>
  </CD>
  <CD>
    <TITLE>Maggie May</TITLE>
    <ARTIST>Rod Stewart</ARTIST>
    <COUNTRY>UK</COUNTRY>
    <COMPANY>Pickwick</COMPANY>
    <PRICE>8.50</PRICE>
    <YEAR>1990</YEAR>
  </CD>
  <CD>
    <TITLE>Romanza</TITLE>
    <ARTIST>Andrea Bocelli</ARTIST>
    <COUNTRY>EU</COUNTRY>
    <COMPANY>polydor</COMPANY>
    <PRICE>10.80</PRICE>
    <YEAR>1996</YEAR>
  </CD>
  <CD>
    <TITLE>When a man loves a woman</TITLE>
    <ARTIST>Percy Sledge</ARTIST>
    <COUNTRY>USA</COUNTRY>
    <COMPANY>Atlantic</COMPANY>
    <PRICE>8.70</PRICE>
    <YEAR>1987</YEAR>
  </CD>
  <CD>
    <TITLE>Black angel</TITLE>
    <ARTIST>Savage Rose</ARTIST>
    <COUNTRY>EU</COUNTRY>
    <COMPANY>Mega</COMPANY>
    <PRICE>10.90</PRICE>
    <YEAR>1995</YEAR>
  </CD>
  <CD>
    <TITLE>1999 Grammy Nominees</TITLE>
    <ARTIST>Many</ARTIST>
    <COUNTRY>USA</COUNTRY>
    <COMPANY>Grammy</COMPANY>
    <PRICE>10.20</PRICE>
    <YEAR>1999</YEAR>
  </CD>
  <CD>
    <TITLE>For the good times</TITLE>
    <ARTIST>Kenny Rogers</ARTIST>
    <COUNTRY>UK</COUNTRY>
    <COMPANY>Mucik Master</COMPANY>
    <PRICE>8.70</PRICE>
    <YEAR>1995</YEAR>
  </CD>
  <CD>
    <TITLE>Big Willie style</TITLE>
    <ARTIST>Will Smith</ARTIST>
    <COUNTRY>USA</COUNTRY>
    <COMPANY>Columbia</COMPANY>
    <PRICE>9.90</PRICE>
    <YEAR>1997</YEAR>
  </CD>
  <CD>
    <TITLE>Tupelo Honey</TITLE>
    <ARTIST>Van Morrison</ARTIST>
    <COUNTRY>UK</COUNTRY>
    <COMPANY>polydor</COMPANY>
    <PRICE>8.20</PRICE>
    <YEAR>1971</YEAR>
  </CD>
  <CD>
    <TITLE>Soulsville</TITLE>
    <ARTIST>Jorn Hoel</ARTIST>
    <COUNTRY>norway</COUNTRY>
    <COMPANY>WEA</COMPANY>
    <PRICE>7.90</PRICE>
    <YEAR>1996</YEAR>
  </CD>
  <CD>
    <TITLE>The very best of</TITLE>
    <ARTIST>Cat Stevens</ARTIST>
    <COUNTRY>UK</COUNTRY>
    <COMPANY>Island</COMPANY>
    <PRICE>8.90</PRICE>
    <YEAR>1990</YEAR>
  </CD>
  <CD>
    <TITLE>Stop</TITLE>
    <ARTIST>Sam brown</ARTIST>
    <COUNTRY>UK</COUNTRY>
    <COMPANY>A and M</COMPANY>
    <PRICE>8.90</PRICE>
    <YEAR>1988</YEAR>
  </CD>
  <CD>
    <TITLE>Bridge of Spies</TITLE>
    <ARTIST>T'Pau</ARTIST>
    <COUNTRY>UK</COUNTRY>
    <COMPANY>siren</COMPANY>
    <PRICE>7.90</PRICE>
    <YEAR>1987</YEAR>
  </CD>
  <CD>
    <TITLE>Private Dancer</TITLE>
    <ARTIST>Tina Turner</ARTIST>
    <COUNTRY>UK</COUNTRY>
    <COMPANY>Capitol</COMPANY>
    <PRICE>8.90</PRICE>
    <YEAR>1983</YEAR>
  </CD>
  <CD>
    <TITLE>Midt om natten</TITLE>
    <ARTIST>Kim larsen</ARTIST>
    <COUNTRY>EU</COUNTRY>
    <COMPANY>Medley</COMPANY>
    <PRICE>7.80</PRICE>
    <YEAR>1983</YEAR>
  </CD>
  <CD>
    <TITLE>Pavarotti gala Concert</TITLE>
    <ARTIST>Luciano Pavarotti</ARTIST>
    <COUNTRY>UK</COUNTRY>
    <COMPANY>DECCA</COMPANY>
    <PRICE>9.90</PRICE>
    <YEAR>1991</YEAR>
  </CD>
  <CD>
    <TITLE>The dock of the bay</TITLE>
    <ARTIST>Otis Redding</ARTIST>
    <COUNTRY>USA</COUNTRY>
    <COMPANY>Stax Records</COMPANY>
    <PRICE>7.90</PRICE>
    <YEAR>1968</YEAR>
  </CD>
  <CD>
    <TITLE>Picture book</TITLE>
    <ARTIST>Simply Red</ARTIST>
    <COUNTRY>EU</COUNTRY>
    <COMPANY>Elektra</COMPANY>
    <PRICE>7.20</PRICE>
    <YEAR>1985</YEAR>
  </CD>
  <CD>
    <TITLE>Red</TITLE>
    <ARTIST>The Communards</ARTIST>
    <COUNTRY>UK</COUNTRY>
    <COMPANY>London</COMPANY>
    <PRICE>7.80</PRICE>
    <YEAR>1987</YEAR>
  </CD>
  <CD>
    <TITLE>Unchain my heart</TITLE>
    <ARTIST>Joe Cocker</ARTIST>
    <COUNTRY>USA</COUNTRY>
    <COMPANY>EMI</COMPANY>
    <PRICE>8.20</PRICE>
    <YEAR>1987</YEAR>
  </CD>
</CRecord>

模型类

<Serializable()>
Public Class CRecord
    Public Property Title() As String
    Public Property Artist() As String
    Public Property Country() As String
    Public Property Price() As Double
    Public Property Year() As Integer
End Class

代码

'' Member Variable
Private m_Records As New List(Of CRecord)

Private Sub btnImport_Click(sender As Object,e As EventArgs) Handles btnImport.Click

    '' Create an instance of the XmlSerializer.
    Dim serializer As New XmlSerializer(GetType(List(Of CRecord)))
    Dim temp As List(Of CRecord)
    '' Declare an object variable of the type to be deserialized.
    Dim record As CRecord = nothing

    Using reader As New FileStream(sXmlPath,FileMode.Open)
        '' Call the Deserialize method to restore the object's state.
        m_Records = CType(serializer.Deserialize(reader),List(Of CRecord))
    End Using
End Sub

解决方法

我假设您不能更改 Xml 结构的任何部分，并且更愿意更改您自己的 VB.Net 代码

我将您的类 CRecord 重命名为 CD，因为它更好地代表了您正在加载的内容，并且 XmlDeserialization 过程会将 Xml 名称与类名称进行匹配。

此外，我为每个属性添加了属性 <XmlElement("...">，因为 Xml 元素名称都是大写的，而 VB.Net 属性不是。您可以选择不添加此属性，但是您需要将属性名称更改为全部大写以匹配 Xml。

所需的最后一点代码是告诉 XmlSerializer 类用于根节点的内容：

New XmlRootAttribute("CRecord")

<Serializable()>
Public Class CD
    <XmlElement("TITLE")>
    Public Property Title() As String

    <XmlElement("ARTIST")>
    Public Property Artist() As String

    <XmlElement("COUNTRY")>
    Public Property Country() As String

    <XmlElement("PRICE")>
    Public Property Price() As Double

    <XmlElement("YEAR")>
    Public Property Year() As Integer
End Class

<TestMethod()>
Public Sub Test_XmlDeserialize()

    Dim m_Records As List(Of CD)

    Dim sXmlPath = "D:\Sample.xml"

    '' Create an instance of the XmlSerializer.
    Dim serializer As New XmlSerializer(GetType(List(Of CD)),New XmlRootAttribute("CRecord"))

    Using reader As New FileStream(sXmlPath,FileMode.Open)
        '' Call the Deserialize method to restore the object's state.
        m_Records = CType(serializer.Deserialize(reader),List(Of CD))
    End Using

通过这些更新，您应该能够根据需要反序列化 Xml。

vb.net vb.net xml xml xml xml xml xml xml xml-serialization