Vb.Net实例化属性的类这是一个不同类

Question

这是序列化和反序列化XML对象

<XmlRoot("orderadd")> 
<Serializable()> _ 
Public Class clsSMsgRequestMessage 
    <XmlElementAttribute()> Public Property ordertype() As String 
    <XmlElementAttribute()> Public Property vehicleid() As String 
    <XmlElementAttribute()> Public Property orderpriority() As String 
    <XmlElementAttribute("orderpart")> Public Property orderpart() As RequestMessageOrderaddOrderpart() 
    <XmlAttributeAttribute()> Public Property clientid() As String 
    <XmlAttributeAttribute()> Public Property transactionid() As String 
    <XmlAttributeAttribute()> Public Property numberoforderparts() As String 

    Public Sub New() 
    End Sub 
End Class 

Public Class RequestMessageOrderaddOrderpart 
    <XmlElementAttribute()> Public Property operation() As String 
    <XmlElementAttribute()> Public Property location() As String 
    <XmlElementAttribute()> Public Property loadtype() As String 
    <XmlAttributeAttribute()> Public Property orderpartnumber() As String 

    Public Sub New() 
    End Sub 

End Class 

这可以正确处理反序列化的目的数组，但现在我想正确创建此对象，以便我可以将其序列化回XML对象。

Dim anotherTest As clsSMsgRequestMessage = New clsSMsgRequestMessage() 
Dim testOrderPart1 As New RequestMessageOrderaddOrderpart 


anotherTest.clientid = "data" 
anotherTest.orderpriority = "data" 
anotherTest.ordertype = "data" 
anotherTest.transactionid = "data" 
anotherTest.vehicleid = "data" 
anotherTest.numberoforderparts = "data" 

testOrderPart1.loadtype = "data" 
testOrderPart1.location = "data" 
testOrderPart1.operation = "data" 
testOrderPart1.orderpartnumber = "data" 


anotherTest.orderpart(0) = testOrderPart1 

这里的最后一行不起作用，因为anotherTest.orderpart（0）还没有实例化。但我不知道如何实例化它，因为

anotherTest.orderpart(0) = New RequestMessageOrderaddOrderPart 

仍然带着“未设置对象实例的对象引用”。

anotherTest.orderpart = New RequestMessageOrderaddOrderPart 

回来了“类型的值不能转换为“的一维数组”

我觉得我在正确的轨道上与由自身实例它像我有做“ testOrderPart1'，但我不知道如何链接到我的另一个测试。订单部分

请帮助！

Answer 1

你必须首先初始化数组属性：

anotherTest.orderpart = New RequestMessageOrderaddOrderPart(10) {} 

10是数组大小。

之后，你就可以设置第一个数组元素：

anotherTest.orderpart(0) = New RequestMessageOrderaddOrderPart 

更新

不过，我想你应该改变你的财产申报成为List(Of RequestMessageOrderaddOrderPart)。随着名单，你不必指定项目的数量：

anotherTest.orderpart = New List(Of RequestMessageOrderaddOrderPart)() 

添加项目是很容易的：

anotherTest.orderpart.Add(new RequestMessageOrderaddOrderPart()) 

而你仍然可以使用索引来获取/修改项目：

Dim firstItem = anotherTest.orderpart(0) 

当然，该项目必须先使用Add方法插入。

List(Of T)也可以正常使用序列化。