Question

Sorry my title is a bit vague, but what I’m trying to do will probably take a paragraph to explain.

At the moment what I’m trying to do is this:

• Gather user in put a from a text box
• Divide the value entered by 2
• Display this new value on a label

So, to get user values I’ve done this:

  private void userLengthTextBox_TextChanged(object sender, EventArgs e)
    {
        _userLength = userLengthTextBox.Text;
    }

This is coming in as a string. Then in a new function, I’m converting this string to a single (need it to be a float), calculating half the value entered and then storing it in a new float.

Like so:

    _oldTlX = Convert.ToSingle(_userLength);
    _tlX = _oldTlX / 2;

Then, when I press a button, I’m trying to get this value to display in a label:

 _valueLabel.Text = Convert.ToString(_tlX);

However, when I press the button, the value remains at 0. No matter what I put. As far as I can see I’ve converted the value I need to the correct format needed, but it is still saying I’m doing it wrong.

Answer 1

I recommend you to use double internally, and then use a format string to show the result in a propper way:

double _oldTlX;
if (!double.TryParse(_userLength, out _oldTlX)) return;
double _tlX = _oldTlX / 2;

_valueLabel.Text = string.Format("{0:f3}", _tlX); // 3 decimal positions

You can also check at the MSDN how to format numeric results.

Hope it helps.