Fix invalid JSON String using regular expression, in PHP

Is easy to visualize the mistake in your JSON encoding analizing the example provided line. There is a pattern , so it can be recovered easilly.

REGEX approach

You can fix your string aplying a 2 stages regexp, the first one to introduce the missing double quotes, and the second, to inject the coma delimiters.

<?php
$str = '{"id_content": "1"name": "Zappos Case Page 1"id_content_type": "1}';
$str = preg_replace( '/"\w+":\s"[\w\s]*/' , '$0"' , $str);
$str = preg_replace( '/""/' , '","' , $str);
echo $str;
?>

STRING MANIPULATION approach

Another approach is by deconstruction, splitting the string, processing the parts, and building the object again:

<?php
$str = '{"id_content": "1"name": "Zappos Case Page 1"id_content_type": "1}';

// remove '{' from the beggining of the string
$str = ltrim($str, '{');
// remove '}' from the end of the string
$str = rtrim($str, '}');
// remove the first '"' from the beggining of the string
$str = ltrim($str, '"');
// split the string in each '"'
$raw = explode('"' , $str);
// prepare an empty array to store valid properties&values
// and store in it the valid keys (removing useless keys ":")
$clean = array();
for ($i = 0; $i < count($raw); $i++) {
  if ( trim( $raw[$i] ) !== ":") array_push( $clean,$raw[$i] );
}
// asumming property names are on odd keys 
// and values in even keys
// we can now create a valid object...
$obj = array();
for ($i = 0; $i < count($clean); $i++) {
  if ( $i % 2 === 0) $obj[ $clean[$i] ] = $clean[$i+1];
}
// and convert it back to JSON notation
$jsonObj = json_encode($obj);
echo $jsonObj;
?>

INPUT (invalid json):

'{"id_content": "1"name": "Zappos Case Page 1"id_content_type": "1}'

OUTPUT (valid json):

'{"id_content":"1","name":"Zappos Case Page 1","id_content_type":"1"}'

This code will only work, if the pattern is always the same. Otherwise, you will have to addapt the code to the different scenarios.

you can validate the json in JS itself by something like.

function isJSON(str) {
    try {
        JSON.parse(str);
    } catch (e) {
        return false;
    }
    return true;
}

if its valid then send to server side and save into DB.

For existing data, you can not do anything. You might need to do correction manually using any online tool (http://json.parser.online.fr/) before saving to DB.