How can I save & extract a json object as a string inside json from PHP to Javascript?

Question

I'm trying to save a string which is encoded as json into another json string.
In particular, I have to be able to handle empty objects: "{}".

PHP:

$sVal = "{}";
$jsonString  = "{\"Var2\":\"My first var\", \"Var2\":\"My second var\", \"MyBlankObject\":\"{}\"}"

...

Javascript:

var oMyJSON = JSON.parse('< ?= $jsonString;? >');

I get a JSON parse error saying an unexpected { was found.

I can see the code in Chrome's debugger.

The brackets are simply removed and in the client side (javascript ) code, the object is replaced with the word null. That's not valid JSON.

,"Properties":null,

This causes javascript to crash.

If I try to json_encode it on the server side (PHP) I get double quotes on each side of the brackets.

,"Properties":""{}"",

I get the same thing if I just add the double quotes: ""{}""

Of course, this causes javascript to crash too.

Once in the client and I have the JSON object intact, I need to be able to extract the 'string' held in the property: MyBlankObject and then decode that JSON into a seperate JSON object.

Everything I've tried fails. How can I accomplish this?

PHP is for hypertext, not script, You'll need to echo $jsonString somewhere in your html first. Then you can access that with javascript. Also, you shouldn't have to escape the double quotes. As is, you don't have valid JSON. — poorly-written-code
– poorly-written-code, Commented Dec 2, 2018 at 17:42
Hmm, according to JSONlint that is valid, as a string. To comment on your second issue, putting quotes around {} makes it a string rather than an object. I think you want something like this {"Var1":"My first var","Var2":"My second var","MyBlankObject":{}} — poorly-written-code
– poorly-written-code, Commented Dec 2, 2018 at 18:00
Never build your JSON string "manually" like you do with $jsonString = . It is bad practice. Always build your objects in the language you are using (PHP), and then use the built-in functions (json_encode) to build JSON. — trincot
– trincot, Commented Dec 19, 2018 at 20:49

Thiago Barcala · Accepted Answer · 2018-12-02 20:28:41Z

3

You can define the object using PHP notation, and let json_encode encode it for you.

$phpArray = [
    'Var2' => 'My first var',
    'Var2' => 'My second var',
    'MyBlankObject' => new \stdClass
];

And then in the JavaScript:

var oMyJSON = JSON.parse('<?= json_encode($phpArray); ?>');

answered Dec 2, 2018 at 20:28

Thiago Barcala

7,4232 gold badges24 silver badges26 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

How can I save & extract a json object as a string inside json from PHP to Javascript?

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related