<div class="form">
    <input type="text" id="idperson"><input type="text" id="name">
    <button id="add" type="button">ADD</button>
</div>
<script src="https://code.jquery.com/jquery-1.12.0.min.js"></script>
<script>
    var people = [];

    $("#add").click(function(){
        var iduser = $("#idperson").val();
        var name = $("#name").val();

        if(people["idperson"]!=iduser){
            people.push({idperson:iduser,nameperson:name});
        }
        console.log(people);
    });
</script>