Question

This seems like it might be a bad idea, but I can’t figure out why:

I have a class, cXYZ, with properties A, B and C. It also has a method ‘sGetData’ that loads those three properties from the database, and a method ‘sSaveData’ which saves it back.

class cXYZ    public property A as string...   public property B as string...   public property B as string..    public sub sGetData()...   public sub sSaveData()...  end class 

A webform has the following property:

private property xyz() as cXYZ get     return session('myXYZ') end get set (value as cXYZ)     session('myXYZ')=value end set end property 

And the following events:

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load  if not ispostback() then     xyz=new cXYZ() end if  end sub  Protected Sub ButtonLoad_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles ButtonLoad.Click     //Can now reference the class   txtA.text=xyz.A   txtB.text=xyz.B   txtC.text=xyz.C  end sub    Protected Sub ButtonSave_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles ButtonSave.Click    //Can now reference the class   xyz.A=txtA.text   xyz.B=txtA.text   xyz.C=txtC.text    xyz.sSaveData()  end sub 

I can see some overhead with serializing/deserializing for each property reference- it might be worth doing this:

 Protected Sub ButtonSave_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles ButtonSave.Click    dim localxyz as cXYZ=xyz    localxyz .A=txtA.text   localxyz .B=txtA.text   localxyz .C=txtC.text    xyz=localxyz  end sub 

Other than that, views on why this is good or bad? The class is not large, it maintains the form state. Webforms suck, etc is not very useful..

Answer 1

I would improve that little bit:

 private _xyz as cXYZ = nothing    private property xyz() as cXYZ     get       if _xyz is nothing then _xyz = TryCast(session('myXYZ'), cXYZ)       return _xyz    end get     set (value as cXYZ)       _xyz = value       session('myXYZ')=_xyz     end set end property