JavaScript parsing boolean

Question

in the response from my server I get a JSON object. It has a boolean flag.

if(file.showInTable == 'true') {

}

But, even if showInTable is set to false, I get inside that code block. How to cope with that ?

I tried:

if(file.showInTable == 'true')
if(file.showInTable)
if(Boolean(file.showInTable))

Edit

as Ghommey has mentioned, I've used the 2nd option to check that value. Even if the comparions statement returns false, it also gets inside the code. See the pic below

enter image description here

Is it set to the boolean value `false` or the string `'false'`? — Anthony Grist, Aug 17 '12 at 08:54
Duplicate of http://stackoverflow.com/questions/263965/how-can-i-convert-a-string-to-boolean-in-javascript — Sergii Stotskyi, Aug 17 '12 at 08:54
@Tony We're going to need to see a lot more code to be able to definitively answer this. Let's see how you're making the call to get the JSON, the JSON response and the code that processes it. — Anthony Grist, Aug 17 '12 at 09:06

score 2 · Answer 1 · answered Aug 17 '12 at 09:01

2

it is set to false or true (as bool) - Tony

Why do you compare a boolean as a string?

Just compare it as a boolean:

if(file.showInTable === true) {

}

or

if(file.showInTable !== false) {

}

answered Aug 17 '12 at 09:01

jantimon

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`file.showInTable === true` and `file.showInTable !== false` aren't the same comparison. `'true' === true` is false, whereas `'true' !== false` is true. – Anthony Grist Aug 17 '12 at 09:05
but Anthony, the thing here is, he receives a boolean object, so file.showInTable will be either `true` or `false` not `'true'` or `'false'`, OP was attempting to equal the boolean he was receiving to a string. – Gonçalo Vieira Aug 17 '12 at 09:14
Was it not the complete opposite? – Jonas G. Drange Aug 17 '12 at 09:15
a strange thing. I've used the 2nd option to check it's value. When it's `true`, it gets inside, but if that comparsion statement returns `false`, it also gets inside – Tony Aug 17 '12 at 10:23

score 1 · Answer 2 · answered Aug 17 '12 at 09:03

1

This is ugly, but why not?

if (file.showInTable === "false") file.showInTable = false;

answered Aug 17 '12 at 09:03

Jonas G. Drange

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JavaScript parsing boolean

Edit

2 Answers2