C# ?: Expression

Question

I have a function with multiple if's (THIS IS NOT THE ACTUAL CODE)

if(n == 1)
   m = 1;
if(n == 2)
   m = 2;
if(n == 3)
   m = 3;

Instead of that I wanted to do make them all into ?: expression :

(n == 1) ? m = 1;

But it says that its expecting a ':'

I am familiar with the ?: expression from C++ where you can simply write:

(n == 1) ? m = 1 : 0;

But 0 doesn't take here. This is a ridiculous question and I couldn't even find an answer in google since it ignores '?:' as a word.

ANSWER : too bad the answer was in the comments. There is no way to "do nothing" in this expression and I should use if-else or switch. thanks.

Answer 1

It looks like you're looking for:

m = (n == 1) ? 1 : 0;

Which you could then cascade to:

m = (n == 1) ? 1 : (n == 2) ? 2 : (n == 3) ? 3 : 0;

An important (to me, anyway), aside:

Why are you asking this? If it's because you think that this form will be more efficient than a series of if statements, or a switch, don't. The C# compiler and the .net JIT compiler are really quite clever and they'll transform your code (hopefully!) into its most optimal form. Write your code so its as understandable by yourself, or the developer who has to maintain it after you as it can be. If the performance you get isn't acceptable, then try changing it around but measure to determine what works best (bearing in mind that newer compilers/.net frameworks could well change what happens).

Answer 2

looking for ternary operator in c# will give you relevant results.

an example usage would be

var m = n == 1 ? 1 : 0