C# for loops text compare

Question

I'm trying to assign a combobox index by looping through the values and finding the one that matches my diameter variable. (the combobox items change based on the diameter, e.g. some pipe types only have 0.5", 1.0" while others may have an intermediate 0.75" value).

The code comparison never seems to go true (so myIndex is never assigned anything outside of the initialization) although when I put a breakpoint on it, the text strings match at the appropriate iteration.

int myIndex = 0;

for (int i = 0; i <= cboDiameter.Items.Count-1; i++)
{
    if (cboDiameter.GetItemText(cboDiameter.Items[i]) == formPipe.diameter.ToString()) 
    {
        //this line never executes, even when there's seemingly a text match
        myIndex = i;
    }
}
cboDiameter.SelectedIndex = myIndex;

This is what I'm using to assign the pipe diameter, but it's being truncated. (e.g. when the combobox text is "1.0", the pipe diameter is being assigned "1"

//assign the value of the dropdown to the object
double.TryParse(cboDiameter.GetItemText(cboDiameter.SelectedItem), out value);
formPipe.diameter = value;

Are you sure `formPipe.diameter.ToString()` returns a string with a `"` in it ? — Shyju, Dec 18 '15 at 23:06
You compare strings. Strings like `1.0` and `1` are not identical. — wimh, Dec 18 '15 at 23:07
you need to use either `.EndsWith` function or `.Contains` and `.Split()` — MethodMan, Dec 18 '15 at 23:08
Wimmel is correct. formPipe.diameter = 1.0, but when I use the .ToString() method, it is truncated to 1. Is there a way to avoid this truncation? — coolhand, Dec 18 '15 at 23:27
Whoever downvoted this, please explain why, so the OP can sate your requirements. Downvoting newbies and not telling them why doesn't help them become better contributors. — kayleeFrye_onDeck, Dec 18 '15 at 23:50

score 1 · Accepted Answer · answered Dec 18 '15 at 23:38

Not 100% sure why the double was being truncated to an integer, but to fix it I parsed the combobox value to another double and just compared the two doubles instead of comparing strings:

for (int i = 0; i <= cboDiameter.Items.Count-1; i++)
                {
                    double.TryParse(cboDiameter.GetItemText(cboDiameter.Items[i]), out val);
                    if (val == formPipe.diameter)
                    {
                        myIndex = i;
                    }
                }

C# for loops text compare

1 Answers1