将XML文件解析为自定义类- InvalidCastException

Question

我有一个自定义的XML文件，看起来像这样，里面有一些'n‘项。我试图将所有的值加载到lst变量上，并对它执行一个foreach循环，以便进一步处理……

  <ItemInfo>
    <StartTime>2014-06-16T00:00:00</StartTime>
    <EndTime>2014-06-16T23:59:59</EndTime>
    <Text>Calendar Project Started</Text>
    <A>255</A>
    <R>255</R>
    <G>0</G>
    <B>0</B>
  </ItemInfo>
  <ItemInfo>
    <StartTime>2014-08-02T00:00:00</StartTime>
    <EndTime>2014-08-02T23:59:59</EndTime>
    <Text>First Release</Text>
    <A>255</A>
    <R>255</R>
    <G>0</G>
    <B>0</B>
  </ItemInfo>

我正在尝试使用Deserialze()方法解析它们。

 Private Sub Form4_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        Dim fi As System.IO.FileInfo = New IO.FileInfo(System.IO.Path.Combine(Application.StartupPath, "items.xml"))
        If fi.Exists Then
            Dim lst As New List(Of ItemInfo)
            Dim serializer As New XmlSerializer(GetType(ItemInfo))
            Dim fs As New IO.FileStream("items.xml", IO.FileMode.Open)
            Dim reader As System.Xml.XmlReader = System.Xml.XmlReader.Create(fs)          
            lst = CTypeDynamic(serializer.Deserialize(reader), lst.GetType)  '->Invalid cast Exception
            fs.Close()
        End If
    End Sub

自定义类如下：

Public Class ItemInfo
    Public StartTime As DateTime
    Public EndTime As DateTime
    Public Text As String
    Public A As Int32
    Public R As Int32
    Public G As Int32
    Public B As Int32
    Dim pattern As HatchStyle
    Dim patternColor As Color

    Public Sub ItemInfo(startTime As DateTime, endTime As DateTime, text As String, color As Color)
        startTime = startTime
        endTime = endTime
        text = text
        A = color.A
        R = color.R
        G = color.G
        B = color.B
    End Sub
End Class

例外消息是：

从类型'ItemInfo‘到类型'List(Of ItemInfo)’的转换无效。

对于我在哪里做错误有什么建议吗？

Answer 1

您使用错误的类型初始化XmlSerializer。

您的XML包含一个项数组，并且尝试将其反序列化为一个List(Of ItemInfo)，因此您应该使用：

Dim serializer As New XmlSerializer(lst.GetType())

而不是

Dim serializer As New XmlSerializer(GetType(ItemInfo))

反序列化为List(Of ItemInfo)，而不是一个ItemInfo。