Question

Is it faster to make a comparison or a cast in C#.Net?
For example:

bool? flag = null;    
...    
if(flag == true)... or if((bool)flag)...  

Also, what is the cost (in memory) of a cast?

Answer 1

If memory serves the compiler will force you to cast the bool? to a bool before using it in the if statement. You might like the null coalesce operator:

//If flag == null then return false, otherwise return the value of flag.
if (flag ?? false)