How to get value of a textbox inside a table inside a tabcon

Question

Hi! can anyone help me how to get the value of a textbox which is inside a table inside a tabcontainer?

 

Below is what I have so far but it doesn't work.

$(document).ready(function () {
        $('#PolicyTxtBox').autocomplete({
            source: '/Handlers/TravelAssuranceHandler.ashx'

        });

    });

Thanks in advance.