jQuery Ajax data show double using append

Question

I'm displaying data to marquee using jQuery ajax.

When the ajax load (every 1 second), the data always show double.

Code:

var messageLen = jsonStr.message.length;

for(var i=0; i<messageLen; i++)
{
    var message = jsonStr.message[i];

    var newOption = $('<li>'+message+'</li>');
    $('#list').append(newOption);
}

HTML

<marquee>
    <ul id="list"></ul>
</marquee>

So, what I want the data show not double.

*I'm using $('#list').html(newOption); it only show 1 data (actual I have more data)

Answer 1

Empty the list before loop

var messageLen = jsonStr.message.length;
$('#list').empty();
for(var i=0; i<messageLen; i++)
{
    var message = jsonStr.message[i];

    var newOption = $('<li>'+message+'</li>');
    $('#list').append(newOption);
}