Making a function parameter a variable within the same function

Question

I want to pass my function's size parameter to be used inside the same function, specifically inside an 'if' statement.

function text_size(size){
    if  (size = '1'){
        alert('something')
    }
    else if (size = '2'){
        alert('something else')
    }
}

This function is called inside another function (didn't write the whole function):

 if (newImg.height > 750, newImg.width > 750){
    text_size('1')
}
else if (newImg.height < 500, newImg.width < 500){{}
    text_size('2')
}

As for now it always alerts 'something' regardless of the parameters.

Tzach · Accepted Answer · 2014-04-10 11:09:00Z

4

Short answer:

Change if (size = '1'){ to if (size == '1'){ (and do the same for the second if).

Longer answer:

size = '1' sets size to '1' and evaluates as '1', which is evaluated as true in javascript. This makes the code inside the first if statement always run.

answered Apr 10, 2014 at 11:09

Tzach

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1 Comment

Andy Over a year ago

Might be helpful if you explain the difference in your answer.

isThisLove · Accepted Answer · 2014-04-10 11:10:54Z

2

function text_size(size){
    if  (size === '1'){
        alert('something')
    }
    else if (size === '2'){
        alert('something else')
    }
}

= assign a value to a variable

== do assertions between left and right conditions of the ==

=== do like == but also check type (string, integer, etc..)

answered Apr 10, 2014 at 11:10

isThisLove

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Comments

phylax · Accepted Answer · 2014-04-10 11:12:11Z

2

if (newImg.height > 750, newImg.width > 750){
  text_size('1')
}

should be (to use logically and, for or its ||):

if (newImg.height > 750 && newImg.width > 750){
  text_size('1')
}

answered Apr 10, 2014 at 11:12

phylax

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Comments

Gwenc37 · Accepted Answer · 2014-04-10 11:13:58Z

0

As @Tzach said, the problem comes from

if  (size = '1'){

You have to use size == '1' instead.

Why? because if you use only one '=', in means that you are doing an assigantion :

var size = 0;
if (size = 1){...}
alert(size); //size is now equal to 1

var size = 0;
if (size == 1){...}
alert(size); //size is equal to 0

answered Apr 10, 2014 at 11:13

Gwenc37

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