c# - What it the easiest way to make LINQ to process all collection at once? -

i have similar constructions:

var t = in enumerable.range(0,5)         select num(i);  console.writeline(t.count()); foreach (var item in t)     console.writeline(item); 

in case linq evaluate num() function twice each element (one count() , 1 output). after such linq calls have declare new vatiable: var t2 = t.tolist();

is there better way this?

you can call tolist without making separate variable:

var t = enumerable.range(0,5).select(num).tolist(); 

edit: or,

var t = enumerable.range(0,5).select(x => num(x)).tolist(); 

or even

var t = (from in enumerable.range(0,5)          select num).tolist();