What is the difference between 2 code (loop for javascript)?

Question

What is the difference between 2 code (loop for javascript) ?

<script>
for(x=0;x<5;x++)
{
alert(x);
}
</script>

AND

<script>
for(x=0;x<5;++x)
{
alert(x);
}
</script>

i tested the result will be same.

But in w3school advice like this

for(x=0;x<5;x++)

Could you please tell me. i can use for(x=0;x<5;x++) and for(x=0;x<5;++x) too ?

First `x` is zero and in the end of loop assign `++`. Second code `x`starts in `1` because first asign `++` and then read the value — Marcos Pérez Gude, Mar 30 '16 at 15:22
`i tested the result will be same.` In this case, maybe. But both are different codes — Marcos Pérez Gude, Mar 30 '16 at 15:23
@MarcosPérezGude Have you tested it. I too thought the same. But seriously the results are same. — Rajaprabhu Aravindasamy, Mar 30 '16 at 15:25
@mongmong There is a answer already in stackoverflow http://stackoverflow.com/questions/6867876/javascript-i-vs-i — Thillai Narayanan, Mar 30 '16 at 15:25
@RajaprabhuAravindasamy I don't need to test it. I know that in this case the result is the same, but it doesn't be the same in another situations. Try to write a while loop with this two variants and maybe you'll obtain different results, depending on the code you'll write — Marcos Pérez Gude, Mar 30 '16 at 15:27
@MarcosPérezGude But the question is about, which one we have to use in for loop the post increment/pre increment, because both will yield the same result at this context/ — Rajaprabhu Aravindasamy, Mar 30 '16 at 15:28
I don't try to answer this exactly question, I try to comment what's the difference between both assignments — Marcos Pérez Gude, Mar 30 '16 at 15:29

score 1 · Answer 1 · answered Mar 30 '16 at 15:28

1

In for loop it's same. Difference is in example like this:

var x = 5;
alert(x++); // alerts 5 and then increments

.

var x = 5;
alert(++x); // increments and then alerts 6

answered Mar 30 '16 at 15:28

Bozidar Sikanjic

717
5
12

score 0 · Answer 2 · edited May 23 '17 at 11:45

0

The i++ and ++i differ only in the value they return, which is ignored when written in the 3rd field of the for loop. In this case, they're exactly the same thing.

The difference between them can be found here.

edited May 23 '17 at 11:45

Community

1
1

answered Mar 30 '16 at 15:27

SlySherZ

1,631
1
16
25

What is the difference between 2 code (loop for javascript)?

2 Answers2