How can I compare multiple variables to a single condition?

Question

I have this:

if (input.Text.ToUpper() == "STOP")

But there are so many possible values that I wouldn't be able to specify them all separately like this:

if (input.Text.ToUpper() == "STOP" || input.Text.ToUpper() == "END")

Is there a way that you can do something like this:

if (input.Text.ToUpper() == "STOP", "END", "NO", "YES")

So that using STOP, END, NO, or YES will do the task?

Using any contains won't work, other times accepted words will have the word STOP and END in them.

Contains does NOT match words that contain the string! So Contain can work. — Emond, Aug 04 '12 at 22:46

score 16 · Answer 1 · answered Aug 04 '12 at 22:43

16

You could use a collection like array and Enumerable.Contains:

var words = new[]{ "STOP", "END", "NO", "YES" };
if(words.Contains(input.Text.ToUpper()))
{
     // ...      
}

answered Aug 04 '12 at 22:43

Tim Schmelter

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Steve · Answer 2 · 2012-08-04T23:13:51.390

5

Perfect situation for a string extension

Add this to a new file

namespace appUtils
{
    public static class StringExtensions
    {
        public static bool In(this string s, params string[] values)
        {
            return values.Any(x => x.Equals(s));
        }
    }
}

and call from your code in this way

if(input.Text.In("STOP", "END", "NO", "YES") == true)
   // ... do your stuff

edited Aug 04 '12 at 23:13

answered Aug 04 '12 at 23:00

Steve

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I think this is ideal. I would add a StringComparison argument to your extension method and your Equals check. – Jeff Reddy Aug 20 '12 at 12:03
Even better would be a generic `In`-extension: http://stackoverflow.com/a/833477/284240 – Tim Schmelter Sep 13 '12 at 15:18

score 4 · Answer 3 · answered Aug 04 '12 at 22:43

4

you can do...

if(new[]{ "STOP", "END", "NO", "YES" }.Contains(input.Text.ToUpper()))

answered Aug 04 '12 at 22:43

Keith Nicholas

43,549
15
93
156

score 1 · Answer 4 · answered Aug 04 '12 at 22:44

You can hold an array of the possible words and match it with the Contains method:

string[] validInput = new string[] { "STOP", "END", "NO", "YES" };

// input is the input you have
if (validInput.Contains(input.Text.ToUpper()))
{
    // Do something
}

GSerjo · Answer 5 · 2012-08-05T02:22:10.400

0

        var tasks = new List<string> { "STOP", "END", "NO", "YES" };
        tasks.Contains(input.Text.ToUpper());

looks better

        var tasks = new List<string> { "stop", "end", "no", "yes" };
        tasks.Exists(x => string.Equals(x, input.Text, StringComparison.OrdinalIgnoreCase));

edited Aug 05 '12 at 02:22

answered Aug 04 '12 at 22:45

GSerjo

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score 0 · Answer 6 · answered Aug 04 '12 at 22:52

0

You could use LINQ to do this. That way if you have both STOP and END in your string, it will pick up on both of them:

var myStringArray= new[]{ "STOP", "END", "NO", "YES" };
var query = myString.Any(x => myStringArray.Contains(x));

answered Aug 04 '12 at 22:52

CodeLikeBeaker

20,682
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score 0 · Answer 7 · answered Aug 04 '12 at 23:00

create extension:

public static class Extension
{
    public static bool EqualsAny(this string item, params string[] array)
    {
        return array.Any(s => item.ToUpper() == s.ToUpper());
    }
}

using:

if (inputText.EqualsAny("STOP", "END", "NO", "YES"))

How can I compare multiple variables to a single condition?

7 Answers7

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