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JavaScript JavaScript Loops, Arrays and Objects Simplify Repetitive Tasks with Loops What are Loops?

Thanitsak Leuangsupornpong
Thanitsak Leuangsupornpong
7,490 Points
Posted by Thanitsak Leuangsupornpong
Thanitsak Leuangsupornpong
7,490 Points

Not understand about add the number?

Why don't we use + to add the number to the counter,but teacher use +=. I don't understand why use"+=".

1 Answer

Iain Diamond
Iain Diamond
29,379 Points
Iain Diamond
Iain Diamond
29,379 Points

It's often thought that programmers are lazy. So having to type

var long_descriptive_variable_name = long_descriptive_variable_name + 1;

is really too much work. To make our lives easier, JavaScript (and some other languages) allows the use of the short-hand syntax:

var long_descriptive_variable_name +=  1;

to do the same thing, but with less typing. :)

Hope this helps. iain