序列化var（jquery）？

I have to use jquery serialize for this var... how to?

    var type = { op:"add" , id_user : <?=$u->id?> , tipo : tipo , description : $("#desc_new_param").val() }
                    $.ajax({type: "POST",cache: false,url: "<?=SYSTEM_WEB_ADMIN?>second.php",data: type,success: function(data) {
                        $("#tab-"+tipo).html(data);
   }});

I assume by serialize you mean convert between string and object. Use the JSON object methods:

var type = { 
    op:"add" , 
    id_user : 1431 , 
    tipo : "tipo something" , 
    description : "some sort of description" 
};

var myTypeString = JSON.stringify(type);

console.log("myTypeString is a "+typeof(myTypeString), myTypeString);

console.log("As a JSON object: ", JSON.parse(myTypeString) );

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