Bug? NumberOfDecimalDigits affects actual value

[Alessandro]

Hi All,

we're evaluating the Telerik Suite of controls for our products. While testing your RadNumericUpDown, I found a rather serious issue (or so it seems): setting the NumberOfDecimalDigits actually rounds the inner value to that precision. I am expecting that the value stays the same and the aforementioned property only affects the DISPLAY of that value.

Code to reproduce:

[Test]
public void Value_NumberDecimalDigitsIsLessThanPrecision_IsNotModified()
{
    _nud.NumberFormatInfo.NumberDecimalDigits = 3;
    _nud.Value = 100.12345;
    _nud.NumberFormatInfo.NumberDecimalDigits = 0;
    Assert.That(_nud.Value, Is.EqualTo(100.12345));
}

this unit test fails with:

Expected: 100.12345000000001d
But was:  100.123d

this means that the value gets immediately truncated to the NumberOfDecimalDigits and then further changes to NumberOfDecimalDigits do not modify it anymore... Really odd!

Can you tell me more about this?

Thanks a lot.

Alessandro

[Yana]

Hi Alessandro,

Thank you for your interest in RadControls for Silverlight.

Actually this behavior of RadNumericUpDown is by design - the reason for this is to avoid showing a wrong value in the control (because when NumberOfDecimalDigits is set, the value is rounded).

We  hope that this is not a major show-stopper for you.

All the best,
Yana
the Telerik team