如何json_decode字符串与特殊字符（“\\”）

I have a problem with encoding and decoding json data. In js I send query with data type 'json', it looks like this:

{\"front\":{\"0\":{\"type\":\"text\",\"width\":\"55px\",\"height\":\"27px\",\"top\":\"151px\",\"left\":\"86px\",\"zIndex\":\"1\",\"svg\":\"<svg width=\\\"54.9375\\\" height=\\\"27.09375\\\" viewBox=\\\"0 0 54.9375 27.09375\\\" xmlns=\\\"http://www.w3.org/2000/svg\\\" xmlns:xlink=\\\"http://www.w3.org/1999/xlink\\\"><g id=\\\"0.7882792934370437\\\"><text fill=\\\"#FF0000\\\" stroke=\\\"none\\\" stroke-width=\\\"0\\\" stroke-linecap=\\\"round\\\" stroke-linejoin=\\\"round\\\" x=\\\"\\\" y=\\\"\\\" text-anchor=\\\"start\\\" font-size=\\\"24px\\\" font-family=\\\"arial\\\" data-textcurve=\\\"1\\\" data-itemzoom=\\\"1 1\\\" data-textspacing=\\\"0\\\"><textPath xmlns:xlink=\\\"http://www.w3.org/1999/xlink\\\" xlink:href=\\\"http://138.68.62.219/Buy-Hanes-T-shirt-PC61LS#textPath-item-0\\\"><tspan dy=\\\"0\\\">Hello</tspan></textPath></text></g><defs><path id=\\\"textPath-item-0\\\" d=\\\"M 0.125 22.117808976867764 A 3093.9720937064453 3093.9720937064453 0 0 1 54.124314613414626 22.117808976867764\\\"></path></defs></svg>\",\"rotate\":0,\"text\":\"Hello\",\"color\":\"#FF0000\",\"fontFamily\":\"arial\",\"align\":\"center\",\"outlineC\":\"none\",\"outlineW\":0}}

Then I save it to cell in MySQL, it looks like this:

{\\&quot;front\\&quot;:{\\&quot;0\\&quot;:{\\&quot;type\\&quot;:\\&quot;text\\&quot;,\\&quot;width\\&quot;:\\&quot;55px\\&quot;,\\&quot;height\\&quot;:\\&quot;27px\\&quot;,\\&quot;top\\&quot;:\\&quot;151px\\&quot;,\\&quot;left\\&quot;:\\&quot;86px\\&quot;,\\&quot;zIndex\\&quot;:\\&quot;1\\&quot;,\\&quot;svg\\&quot;:\\&quot;&lt;svg width=\\\\\\&quot;54.9375\\\\\\&quot; height=\\\\\\&quot;27.09375\\\\\\&quot; viewBox=\\\\\\&quot;0 0 54.9375 27.09375\\\\\\&quot; xmlns=\\\\\\&quot;http:\/\/www.w3.org\/2000\/svg\\\\\\&quot; xmlns:xlink=\\\\\\&quot;http:\/\/www.w3.org\/1999\/xlink\\\\\\&quot;&gt;&lt;g id=\\\\\\&quot;0.7882792934370437\\\\\\&quot;&gt;&lt;text fill=\\\\\\&quot;#FF0000\\\\\\&quot; stroke=\\\\\\&quot;none\\\\\\&quot; stroke-width=\\\\\\&quot;0\\\\\\&quot; stroke-linecap=\\\\\\&quot;round\\\\\\&quot; stroke-linejoin=\\\\\\&quot;round\\\\\\&quot; x=\\\\\\&quot;\\\\\\&quot; y=\\\\\\&quot;\\\\\\&quot; text-anchor=\\\\\\&quot;start\\\\\\&quot; font-size=\\\\\\&quot;24px\\\\\\&quot; font-family=\\\\\\&quot;arial\\\\\\&quot; data-textcurve=\\\\\\&quot;1\\\\\\&quot; data-itemzoom=\\\\\\&quot;1 1\\\\\\&quot; data-textspacing=\\\\\\&quot;0\\\\\\&quot;&gt;&lt;textPath xmlns:xlink=\\\\\\&quot;http:\/\/www.w3.org\/1999\/xlink\\\\\\&quot; xlink:href=\\\\\\&quot;http:\/\/138.68.62.219\/Buy-Hanes-T-shirt-PC61LS#textPath-item-0\\\\\\&quot;&gt;&lt;tspan dy=\\\\\\&quot;0\\\\\\&quot;&gt;Hello&lt;\/tspan&gt;&lt;\/textPath&gt;&lt;\/text&gt;&lt;\/g&gt;&lt;defs&gt;&lt;path id=\\\\\\&quot;textPath-item-0\\\\\\&quot; d=\\\\\\&quot;M 0.125 22.117808976867764 A 3093.9720937064453 3093.9720937064453 0 0 1 54.124314613414626 22.117808976867764\\\\\\&quot;&gt;&lt;\/path&gt;&lt;\/defs&gt;&lt;\/svg&gt;\\&quot;,\\&quot;rotate\\&quot;:0,\\&quot;text\\&quot;:\\&quot;Hello\\&quot;,\\&quot;color\\&quot;:\\&quot;#FF0000\\&quot;,\\&quot;fontFamily\\&quot;:\\&quot;arial\\&quot;,\\&quot;align\\&quot;:\\&quot;center\\&quot;,\\&quot;outlineC\\&quot;:\\&quot;none\\&quot;,\\&quot;outlineW\\&quot;:0}}

When I read with php this data that's what I see ( $tmp=$products[0]['design_file']; print_r($tmp);) :

"{\\"front\\":{\\"0\\":{\\"type\\":\\"text\\",\\"width\\":\\"55px\\",\\"height\\":\\"27px\\",\\"top\\":\\"151px\\",\\"left\\":\\"86px\\",\\"zIndex\\":\\"1\\",\\"svg\\":\\"<svg width=\\\\\\"54.9375\\\\\\" height=\\\\\\"27.09375\\\\\\" viewBox=\\\\\\"0 0 54.9375 27.09375\\\\\\" xmlns=\\\\\\"http:\/\/www.w3.org\/2000\/svg\\\\\\" xmlns:xlink=\\\\\\"http:\/\/www.w3.org\/1999\/xlink\\\\\\"><g id=\\\\\\"0.7882792934370437\\\\\\"><text fill=\\\\\\"#FF0000\\\\\\" stroke=\\\\\\"none\\\\\\" stroke-width=\\\\\\"0\\\\\\" stroke-linecap=\\\\\\"round\\\\\\" stroke-linejoin=\\\\\\"round\\\\\\" x=\\\\\\"\\\\\\" y=\\\\\\"\\\\\\" text-anchor=\\\\\\"start\\\\\\" font-size=\\\\\\"24px\\\\\\" font-family=\\\\\\"arial\\\\\\" data-textcurve=\\\\\\"1\\\\\\" data-itemzoom=\\\\\\"1 1\\\\\\" data-textspacing=\\\\\\"0\\\\\\"><textPath xmlns:xlink=\\\\\\"http:\/\/www.w3.org\/1999\/xlink\\\\\\" xlink:href=\\\\\\"http:\/\/138.68.62.219\/Buy-Hanes-T-shirt-PC61LS#textPath-item-0\\\\\\"><tspan dy=\\\\\\"0\\\\\\">Hello<\/tspan><\/textPath><\/text><\/g><defs><path id=\\\\\\"textPath-item-0\\\\\\" d=\\\\\\"M 0.125 22.117808976867764 A 3093.9720937064453 3093.9720937064453 0 0 1 54.124314613414626 22.117808976867764\\\\\\"><\/path><\/defs><\/svg>\\",\\"rotate\\":0,\\"text\\":\\"Hello\\",\\"color\\":\\"#FF0000\\",\\"fontFamily\\":\\"arial\\",\\"align\\":\\"center\\",\\"outlineC\\":\\"none\\",\\"outlineW\\":0}}

If I do this:

$tmp=$products[0]['design_file'];
$info=json_decode($tmp);
print_r($info);

It gives me Null. How can I get my array back from that mess?

Javascript sending:

jQuery(document).triggerHandler( "before.addtocart.design", datas);
var finaldata=JSON.stringify(datas);
    jQuery.ajax({
    url: 'index.php?route=checkout/cart/add', //URL TO CONTROL FUNCTION add()
    type: 'post',
    data: 'product_id=' + product_id + '&quantity=' + q+"&option['options']="+finaldata,

Read in Php

if (isset($this->request->post['option'])) {
            $option = array_filter($this->request->post['option']);

Pass to view

$data['products'][] = array(
                'design_file'=>$product['design_file'],
...
$tmp=$products[0]['design_file'];

You might be storing malformed JSON data. Take a look at these pages (some useful resources right from PHP docs):

PS.: The second link is related to the options parameter used in json_encode. You might compose those values the way you want, just like the example below:

$obj = [
  "prop1" => 123,
  "prop2" => [
    "prop2.1" => "Value A",
    "prop2.2" => [1, 2, 3, 4, 5]
  ]
];

$jsonContent = json_encode($obj, JSON_PRETTY_PRINT | JSON_HEX_TAG | JSON_HEX_APOS | JSON_HEX_QUOT | JSON_HEX_AMP);

By the way, you still can send your JavaScript objects to the server using a contentType: 'application/json' setting in $.ajax function call. That will enable you to handle request data from that HTTP request as a PHP object, as it really should be.

Use PHP to serialize your JSON content in order to store it in database instead of bypassing the string directly from the request attributes.

Something is really messed up here. First, your initial JSON is not valid. Somehow it is already has extra slashes.

Check here: Issue with JSON.stringify adding a extra \ and "" to my Json object. Maybe here: JSON.stringify escaping without need

Also there is missing } in the very end of JSON string (it should be }}} three closing brackets).

Secondly, I guess before you inserted it in database you escaped it (so thats how you got even more slashes) and you did htmlspecialchars(). Considering this, thats how you can parse it in object.

$info = json_decode(stripslashes(htmlspecialchars_decode($tmp.'}')));