Handling a conditional statement in a single line

Question

Is it possible to write following C# code in a line without if and else?

string res = "";

if (!string.IsNullOrEmpty(var1))
    res = string.Format("{0}/{1}", var1, var2);
else
    res = var2;

you're looking for the [ternary operator](https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/operators/conditional-operator) — Jonesopolis, Mar 05 '20 at 13:08
You can quickly find that by googling terms like those in the title of your question, (along with 'C#', even if the same operator exists in many languages anyway) https://idownvotedbecau.se/noresearch/ — Pac0, Mar 05 '20 at 13:09
string res = string.IsNullOrEmpty(var1) ? var2 : string.Format("{0}/{1}", var1, var2) ; — Zeeshan, Mar 05 '20 at 13:11

Berkay · Accepted Answer · 2020-03-05T13:15:16.520

3

Try this,

string res = !string.IsNullOrEmpty(var1) ? string.Format("{0}/{1}", var1, var2) : var2;

Basically, (if this statement is true (like if block's condition part)) ? (this section works) : ((else) this section works);

Hope this helps,

edited Mar 05 '20 at 13:15

answered Mar 05 '20 at 13:07

Berkay

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As OP does not know what the ternary operator is, perhaps it would be prudent to include an explanation in this answer? – Martin Mar 05 '20 at 13:11
1

You are right, tried to explain basically. @Martin – Berkay Mar 05 '20 at 13:15

elvira.genkel · Answer 2 · 2020-03-05T13:32:21.270

2

The conditional operator ?:, also known as the ternary conditional operator, evaluates a Boolean expression and returns the result of one of the two expressions, depending on whether the Boolean expression evaluates to true or false. The syntax for the conditional operator is as follows:

condition ? consequent : alternative

So the code line you are requested is

string res = !string.IsNullOrEmpty(var1) ? string.Format("{0}/{1}", var1, var2) : var2;

edited Mar 05 '20 at 13:32

answered Mar 05 '20 at 13:07

elvira.genkel

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As OP clearly does not know what the ternary operator is, perhaps it would be prudent to include an explanation in this answer? – Martin Mar 05 '20 at 13:11
1

Added explanation, thanks – elvira.genkel Mar 05 '20 at 13:32

score 1 · Answer 3 · answered Mar 05 '20 at 13:11

1

Tecnically, you can hide if within ternary operator ?:

  string res = $"{(!string.IsNullOrEmpty(var1) ? $"{var1}/" : "")}{var2}";

but what for?

answered Mar 05 '20 at 13:11

Dmitry Bychenko

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Handling a conditional statement in a single line

3 Answers3