How to get Value in dynamic generated Textbox - vb.net

Question

I'm new to Visual Basic.
I have a little program look like this.
https://www.dropbox.com/s/xr44pxp3n79atkk/wall.png
It will calculate the total area by adding up all wall area.
Public Sub btnWallAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnWallAdd.Click
FlowLayoutPanel1.Controls.Clear()
FlowLayoutPanel1.AutoScroll = True
For i As Integer = 1 To Val(txtWallNo.Text)
Dim Width As New TextBox()
Dim Height As New TextBox()
Width.Name = "Width" & i
Width.Text = Width.Name
Height.Name = "Height" & i
Height.Text = Height.Name
FlowLayoutPanel1.Controls.Add(Width)
FlowLayoutPanel1.Controls.Add(Height)
Next
End Sub
I have successfully create dynamic textbox base on the number entered by user but I don't know how to get values from those textbox an add them up. Please teach me how do it. Thank you very much!
Sorry for my English!

Answer 1

You can access the controls by name, like this:
Dim txtWidth As TextBox = FlowLayoutPanel1.Controls.Item("Width" & i)
Or, if you have option strict turned on, you need to be explicit about the type conversions:
Dim txtWidth As TextBox = CType(FlowLayoutPanel1.Controls.Item("Width" & i.ToString()), TextBox)
For instance, to add up the area on all the walls, you could do something like this:
Public Sub btnCalculate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCalculate.Click
Dim totalArea As Decimal = 0
For i As Integer = 1 To Val(txtWallNo.Text)
Dim txtWidth As TextBox = CType(FlowLayoutPanel1.Controls.Item("Width" & i.ToString()), TextBox)
Dim txtHeight As TextBox = CType(FlowLayoutPanel1.Controls.Item("Height" & i.ToString()), TextBox)
totalArea = totalArea + (Decimal.Parse(txtHeight.Text) * Decimal.Parse(txtWidth.Text))
Next
lblResult.Text = totalArea.ToString()
End Sub