How to use if-else or switch operator in Assembly? - if-statement

Question

How do I use multiple if-else statements or the switch operator from C/C++ in Assembly?
Something like this in C:
if ( number == 2 )
printf("TWO");
else if ( number == 3 )
printf("THREE");
else if ( number == 4 )
printf("FOUR");
Or using switch:
switch (i)
{
case 2:
printf("TWO"); break;
case 3:
printf("THREE"); break;
case 4:
printf("FOUR"); break;
}
Thanks.

Answer 1

Architecture is critical for specifics but here's some psuedo code which does what you want.
... # your code
jmp SWITCH
OPTION1:
... # do option 1
jmp DONE
OPTION2:
... # do option 2
jmp DONE
Option3:
... # do option 3
jmp DONE
SWITCH:
if opt1:
jmp OPTION1
if opt2:
jmp OPTION2
if opt3:
jmp OPTION3
DONE:
... #continue your program

Answer 2

A detailed answer will depend upon the particular machine instruction set for which you are writing the assembly language. Basically you write assembly code to perform the C language series of tests (if statements) and branches.
In pseudo-assembly it might look like this:
load r1, number // load the value of number into register 1
cmpi r1, 2 // compare register 1 to the immediate value 2
bne test_for_3 // branch to label "test_for_3" if the compare results is not equal
call printf // I am ignoring the parameter passing here
... // but this is where the code goes to handle
... // the case where number == 2
branch the_end // branch to the label "the_end"
test_for_3: // labels the instruction location (program counter)
// such that branch instructions can reference it
cmpi r1, 3 // compare register 1 to immediate value 3
bne test_for_4 // branch if not equal to label "test_for_4"
... // perform printf "THREE"
branch the_end // branch to the label "the_end"
test_for_4: // labels the instruction location for above branch
cmpi r1, 4 // compare register 1 to immediate value 4
bne the_end // branch if not equal to label "the_end"
... // perform printf "FOUR"
the_end: // labels the instruction location following your 3 test for the value of number