Convert string to list of custom objects - asp.net

Question

Say I have an object Fish with properties like
Public Property ID As Integer
Public Property Name As String
Public Property Type As Integer
Public Property Age As Integer
And I have a string that looks like this:
"Fishes[0].ID=1&Fishes[0].Name=Fred&Fishes[0].Type=1&Fishes[0].Age=3&Fishes[1].ID=2&Fishes[1].Name=George&Fishes[1].Type=2&Fishes[1].Age=5&..."
Is there any way of converting/casting/whatever my string into a list of Fish objects? I can't seem to find anything to help. I do have some control over the format of the string if that would make things easier.
Many thanks

Answer 1

What you need to do is to parse the input string to look for Fishes[X].PROPNAME=VALUE pattern. Loop through all matches found in the string and add into or set the existing object in Dictionary. Use X as each object key in the Dictionary.
Create Fish structure:
Structure Fish
Public ID As String
Public Name As String
Public Type As Integer
Public Age As Integer
End Structure
Codes to process the input string:
Dim Fishes As New Dictionary(Of String, Fish)
Dim m As Match = Regex.Match(str, "Fishes\[(?<key>\d+)]\.(?<prop>.+?)=(?<value>[^&]+)", RegexOptions.IgnoreCase)
Do While m.Success
Dim key As String = m.Groups("key").Value.Trim.ToUpper
Dim prop As String = m.Groups("prop").Value.Trim.ToUpper
Dim value As String = m.Groups("value").Value
' if the key not yet exist in the Dictionary, create and add into it.
If Not Fishes.ContainsKey(key) Then
Fishes.Add(key, New Fish)
End If
Dim thisFish As Fish = Fishes(key) ' get the Fish object for this key
' determine the object property to set
Select Case prop
Case "ID" : thisFish.ID = value
Case "NAME" : thisFish.Name = value
Case "TYPE" : thisFish.Type = CInt(value)
Case "AGE" : thisFish.Age = CInt(value)
End Select
Fishes(key) = thisFish ' since the Fish object is declared as Structure,
' update the Dictionary item of key with the modified object.
' If Fish is declared as Class, then this line is useless
m = m.NextMatch()
Loop

Answer 2

Try this ..
Structure Test
Dim ID As String
Dim Name As String
Dim Type As Integer
Dim Age As Integer
End Structure
In your Button click event ..
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim Fishes As New List(Of Test)
Dim Fish As New Test
Fish.ID = "GF"
Fish.Name = "Gold Fish"
Fish.Age = 1
Fish.Type = 1
Fishes.Add(Fish)
MsgBox(Fishes(0).Name)
End Sub

Answer 3

this is vb.net converted
Public Partial Class test
Inherits System.Web.UI.Page
Protected Sub Page_Load(sender As Object, e As EventArgs)
If Not IsPostBack Then
End If
End Sub
Public Sub MYtest()
Dim ls As New List(Of Fish)()
Dim f As New Fish()
f.ID = 1
f.Name = "My name"
f.Type = "My type"
f.Age = 20
ls.Add(f)
End Sub
End Class
Public Class Fish
Public Property ID() As Integer
Get
Return m_ID
End Get
Set
m_ID = Value
End Set
End Property
Private m_ID As Integer
Public Property Name() As String
Get
Return m_Name
End Get
Set
m_Name = Value
End Set
End Property
Private m_Name As String
Public Property Type() As String
Get
Return m_Type
End Get
Set
m_Type = Value
End Set
End Property
Private m_Type As String
Public Property Age() As Integer
Get
Return m_Age
End Get
Set
m_Age = Value
End Set
End Property
Private m_Age As Integer
End Class

Answer 4

In the comments you mentioned that this is via ASP.Net MVC. The ModelBinder will do everything for you.
public ActionResult UpdateFish(IList<Fish> listOfFish)
{
//the ModelBinder will figure out that the user has posted a list of Fish instances.
//do something with listOfFish
return View(listOfFish);
}