How can I do arithmetic operations in one text box?

Question

For example, I write in TextBox1

4*5 or 3-2

how to make an answer in the same text box?

I tried this, but it still didn't work

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
 textbox1.text = val(textbox1.text)
end sub

it just shows the first number

Answer 1

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