How can I remove an item from a listbox without using "Contains"?

Question

I've got this code:

for (int i = listboxWork.Items.Count-1; i > -1; i--) 
{
    if (listboxWork.Items[i].Contains(tblSent))
    {
        listboxWork.Items.RemoveAt(i);
    }
}

...which I derived from here, but my creaky old version of .NET (or maybe it's my puny version of .NET (Compact Framework) that's the problem) doesn't contain "Contains".

I reckon I could replace that line with:

if (listboxWork.Items[i].ToString().IndexOf(tblSent) > -1)

...but am not overly confident that's the best way to do it. Is there a more acceptable way?

array might not have a contains operator, but are you sure that a list object doesnt? You could reverse the list and do a foreach. — crthompson, Oct 07 '14 at 18:15

competent_tech · Accepted Answer · 2014-10-07T18:52:09.983

2

Items is a collection of objects, so you need to convert the element you are working with to a string before you can use Contains:

if (listboxWork.Items[i].ToString().Contains(tblSent))

Edit: since this is CompactFramework (which I failed to recognize in the post originally, the proper solution is to use String.IndexOf, which was already identified.

This is a perfectly acceptable mechanism, but if the CF supports it, I would strongly suggest using a case-insensitive comparison, especially if there is any user input involved in the evaluation:

if (x.Items[0].ToString().ToLower().IndexOf(tblSent.ToLower()) != -1)

edited Oct 07 '14 at 18:52

answered Oct 07 '14 at 18:18

competent_tech

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That is sensible, but even doing it that way (the right way) is impossible in this Contains-challenged version of .NET I'm stuck with. – B. Clay Shannon-B. Crow Raven Oct 07 '14 at 18:22
1

@B.ClayShannon: I overlooked the CF issue earlier; you might want to adjust the tags in your question to include this. I have updated my answer with more info. – competent_tech Oct 07 '14 at 18:29
Well, that's disappointing. I forgot how limiting CF was. Final approach (if the comparison does involve user input) is to convert everything to lowercase (or upper) prior to performing the comparison. I have updated the answer with this approach. – competent_tech Oct 07 '14 at 18:53
1

Yes; CF stands for Cheesy and Frustrating. – B. Clay Shannon-B. Crow Raven Oct 07 '14 at 18:59

How can I remove an item from a listbox without using "Contains"?

1 Answers1