Creating Custom Objects at runtime in C#

Question

I want to create custom objects in C# at runtime, the objects will have properties imported from an xml file. The xml file looks something like this:

<field name="FirstName" value="Joe" type="string" />
<field name="DateAdded" value="20090101" type="date" />

I would like to create objects in c# that have properties such as FirstName and DateAdded and that have the correct type for the properties. How can I do this? I have tried using a function with if statements to determine the type based on the "type" attribute but I would like to evaluate the types on the fly as well.

Thanks.

Answer 1

You can do this via CodeDOM, or more easily using dynamic and ExpandoObject.

However, realize that, without knowing the types in advance, it's difficult to use them effectively. Often, making a Dictionary<TKey, TValue> or similar option is an easier choice.

Answer 2

Sorry, my C#'s rusty, so Ill tackle this in VB. Only way I can figure to do it is to use an Object type. Check out the property type definition and instantiation method below:

Private m_myVal As Object
Public Property myVal() As Object
    Get
        Return m_myVal
    End Get
    Set(ByVal value As Object)
        m_myVal = value
    End Set
End Property

Public Sub New(ByVal valType As String, ByVal val As Object)
    If valType = "string" Then
        myVal = CType(val, String)
    ElseIf valType = "date" Then
        myVal = CType(val, Date)
    End If
End Sub

Then, for example, create a new instance of the class as:

Dim myDynamicClass as New Class1("date","10/21/2010")

Your myval property will have a date typed value stored.