textbox format to decimal?

i have a textbox which i required it to be of either a currency or decimal value.

amtvalue = FormatNumber$(Val(amttb.text, 2)

had been using this formula to do the checking and converting and i realise tat i can't realli fully convert the string into a decimal.

example:
if value of amttb.text is "dsa.32", output for amtvalue will be 0.00

however, if amttb.text is "123.fsdf", output for amtvalue will be 123.00

is there another way for mi to do the check and make it such tat even if the input is "123.fsdf", the output will still be 0.00?

vb.net Code:

Private Sub Button2_Click( _
    ByVal sender As System.Object, _
    ByVal e As System.EventArgs _
) Handles Button2.Click
 
    Dim str As String = "adc.123"
    'Dim str As String = "123.adc"
    Dim value As Single
 
    Single.TryParse(str, value)
    MessageBox.Show(value.ToString("0.00"))
End Sub

Code:

---

        'if value of amttb.text is "dsa.32", output for amtvalue will be 0.00
        'however, if amttb.text is "123.fsdf", output for amtvalue will be 123.00
        Dim testV() As String = New String() {"dsa.32", "123.fsdf", "123.12"}
        Dim amttb As New TextBox
        Dim amtvalue As Decimal
        For x As Integer = 0 To testV.Length - 1 'do the testV
            amttb.Text = testV(x)
            If Decimal.TryParse(amttb.Text, amtvalue) Then
                Debug.WriteLine("number " & amtvalue.ToString("C"))
                Debug.WriteLine("number " & amtvalue.ToString("F2"))
            Else
                Debug.WriteLine("not number " & amtvalue.ToString("C"))
                Debug.WriteLine("not number " & amtvalue.ToString("F2"))
            End If
        Next

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