CallByName multiple property levels?

[Graff]

I want to add attributes to 24 textboxes but am not sure how to go about it.

I have

for i = 1 to 24
    CallByName("textbox"+i,"attributes.add",CallType.Method,"'onclick','CheckTxtBox(this)'")
next i

And it throws up on this saying

Exception Details: System.MissingMemberException: Public member 'Attributes.Add' on type 'String' not found.

[MissingMemberException: Public member 'Attributes.Add' on type 'String' not found.]
Microsoft.VisualBasic.CompilerServices.LateBinding.InternalLateCall(Object o, Type objType, String name, Object[] args, String[] paramnames, Boolean[] CopyBack, Boolean IgnoreReturn) +883
Microsoft.VisualBasic.Interaction.CallByName(Object ObjectRef, String ProcName, CallType UseCallType, Object[] Args) +48
imac.WebForm1.Page_Load(Object sender, EventArgs e) in C:\Documents and Settings\Jared\VSWebCache\index.aspx.vb:109
System.Web.UI.Control.OnLoad(EventArgs e) +67
System.Web.UI.Control.LoadRecursive() +35
System.Web.UI.Page.ProcessRequestMain() +731

I'm pretty sure it doesn't want me putting in more than just attributes but I need to access the add.... Help would be appriciated.