decimal problems

[cdubb07]

when i do a math formula in my code such as i*1 it works but when i use a decimal such as i*.1 the answer is wrong, any suggestions? here's my code:

Function result(ByVal i As Integer) As Integer
Dim x As Integer
x = i * 914.4
Return x
End Function
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
MessageBox.Show(result(Integer.Parse(TextBox1.Text)).ToString())
End Sub
End Class

[mendhak]

Dim x as Decimal.

[mendhak]

Oh, and change the return type of the function to Decimal too. Integers cannot hold points. They are dumb, kinda like blondes.

[FYRe]

Doing a math formula such as " i*1 " certainly works because you declared the variable "i" as an Integer.
However, when using arithmetic problems such as " i*.1 ", variable "i" will be invalid. This is because, earlier, you declared "i" As an Integer.

In Visual Basic, decimal numbers are rather known as "Floating-Point numbers".

Therefore, instead of using Integer to declare "i", you should use either of the following:

- Single (4 bytes)
- Double (8 bytes)
- Decimal (16 bytes)

Therefore, here's a solution :

--------------------------------------------------------------------------

Function result(ByVal i As Double) As Integer

' ---> your codes here <---

End Function

--------------------------------------------------------------------------


thks,
FYRe

[jmcilhinney]

You can multiply an Integer by a floating-point (Single, Double) or fixed-point (Decimal) value without a problem, but if you want to return the result as a foating- or fixed-point value then you cannot assign it to an Integer. With Option Strict turned Off it will be implicitly converted to an Integer by either truncating or rounding (I'm not sure which and I couldn't be bothered checking, suffice to say it's a bad idea). With Option Strict turned On it will refuse to compile without an explicit conversion. What this means is that it is fine to declare the method argument as Integer as long as it is only Integers you want to pass in. You would absolutely need to declare the methdo return type as either Single, Double or Decimal and assign the result of your calculation to a variable of the same type, as mendhak suggested.

I strongly suggest that you always turn Option Strict On to help avoid this type of error. If you would like to do this, right-click the project in the Solution Explorer and select Properties. The set Common Properties -> Build -> Option Strict to On. You may well find that there are quite a few compilation errors in your code after that. These are all the places where you are allowing implicit conversions to occur, which can be the source of unexpected run time errors. You should then go through and explicitly convert the values if appropriate or change your code if the conversion is not appropriate.