将SQL更新查询转换为json请求

I have an sql update query like this; please note that I just have a string of the query like $query:

$query = 'UPDATE "public"."activity" SET "itemid" = 2, "itemname" = 'sssd' WHERE "id" = 19';

From this stringified query, I can get the set clause separately as:

$setClause = '"itemid" = 2, "itemname" = 'sssd'';

I need to convert this set clause to a json array to send in an ajax request like:

{
    "itemid": 2,
    "itemname": "sssd"
  }

So far I havent been able to figure this out; I looked online for a solution as well but couldn't find one. Any ideas please?

This did the job for me. Thanks to John Halbert for pointing it out in the comments.

public function GetJsonFromUpdateSetClause($setClause){
        $sc2JSON1 = '{' . str_replace('=', ':', $setClause) . '}';
        $sc2JSON2 =  str_replace('\'', '\"', $sc2JSON1) ;
        $sc2JSON3 = stripcslashes($sc2JSON2);
        return $sc2JSON3;
    }