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LucaMs said:

B4A, of course

B4X:

Dim D As Double = 1250.60
D = D * 100
Log("D = " & D)

What the result will be?


And this?:

B4X:

Dim D As Double = 1250.60
Dim L As Long = D * 100
Log("D = " & D)
Log("L =: " & L)

https://www.b4x.com/android/forum/threads/trasformare-un-importo-in-un-intero.58999/

Spoiler: VB.Net

B4X:

  Private Sub Form1_Load(sender As Object, e As System.EventArgs) Handles Me.Load
      Dim D As Double = 1250.6
      D = D * 100
      Debug.Write(D)
      Application.Exit()
End Sub

Result: 125060

Click to expand...

Informatix said:

It is due to Java, not to B4A.

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Informatix said:

Note that you will get the right result with a float.

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Informatix said:

As D * 100 is rounded down when converted to a long, the wrong result is pretty logical for L.

Click to expand...

    Private Sub Form1_Load(sender As Object, e As System.EventArgs) Handles Me.Load
        Dim D As Double = 1250.6
        Dim L As Long = D * 100
        D = D * 100
        Debug.WriteLine(D)
        Debug.WriteLine(L)
        Application.Exit()
    End Sub

Informatix said:

If you want to control the precision, never use floats or doubles, only the BigDecimal class (in Java) or as I saw in real applications using currencies, convert everything to long for your computations and use floats or doubles only for the display (by dividing the integer value).

Click to expand...