Dynamic textbox error

Hi, I have trying to create a dynamic textbox. I have created a textbox to allow user to key in how many textbox he wants. Ie, if he key in 3, then 3 textbox will be created. I found the below code from the internet. I tried it and it reached line 4, i got an error saying "Public member 'id' on type 'TextBox' not found.". May I know what went wrong there?1 Dim i As Integer
2 For i = 1 To CType(TxtTotalItem.Text, Integer)
3 Dim letterTbx = New TextBox
4 letterTbx.id = "txt" & i
5 Panel1.Controls.Add(letterTbx)
6 Next
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