Hi nauna,

Refer below code.

HTML

<div class="container">
    <div class="row form margintb white-bg padding15 radius">
        <div class="col-md-4 ">
            <div class="form-group">
                Current Location:                  
                <asp:TextBox ID="txtSource" Enabled="false" runat="server" Text="Bandra, Mumbai, India"></asp:TextBox>
            </div>
            <div class="form-group">
                Destination:                        
                <asp:TextBox ID="txtDestination" Enabled="false" runat="server" Text="Andheri, Mumbai, India"></asp:TextBox>
            </div>
            <div class="form-group">
                <div id="dvDistance">
                </div>
            </div>
        </div>
        <div class="col-md-8">
            <div id="dvMap" style="width: 100%; height: 300px">
            </div>
            <div id="dvPanel" style="width: 100%;">
            </div>
        </div>
    </div>
</div>
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js"></script>
<script type="text/javascript" src="https://maps.googleapis.com/maps/api/js?libraries=places&key=API_Key"></script>
<script type="text/javascript">
    var directionsDisplay;
    var directionsService = new google.maps.DirectionsService();
    google.maps.event.addDomListener(window, 'load', function () {
        new google.maps.places.SearchBox(document.getElementById('<%=txtSource.ClientID%>'));
        new google.maps.places.SearchBox(document.getElementById('<%=txtDestination.ClientID%>'));
        directionsDisplay = new google.maps.DirectionsRenderer({ 'draggable': true });
    });
    var mumbai = new google.maps.LatLng(18.9750, 72.8258);
    var mapOptions = { zoom: 7, center: mumbai };
    var map = new google.maps.Map(document.getElementById('dvMap'), mapOptions);

    function GetRoute() {
        var source, destination;
        source = document.getElementById('<%=txtSource.ClientID%>').value;
        destination = document.getElementById('<%=txtDestination.ClientID%>').value;
        directionsDisplay.setMap(map);
        directionsDisplay.setPanel(document.getElementById('dvPanel'));
        var request = {
            origin: source,
            destination: destination,
            travelMode: google.maps.TravelMode.DRIVING
        };
        directionsService.route(request, function (response, status) {
            if (status == google.maps.DirectionsStatus.OK) {
                directionsDisplay.setDirections(response);
            }
        });

        var service = new google.maps.DistanceMatrixService();
        service.getDistanceMatrix({
            origins: [source],
            destinations: [destination],
            travelMode: google.maps.TravelMode.DRIVING,
            unitSystem: google.maps.UnitSystem.METRIC,
            avoidHighways: false,
            avoidTolls: false
        }, function (response, status) {
            if (status == google.maps.DistanceMatrixStatus.OK && response.rows[0].elements[0].status != "ZERO_RESULTS") {
                var distance = response.rows[0].elements[0].distance.text;
                var duration = response.rows[0].elements[0].duration.text;
                var dvDistance = document.getElementById("dvDistance");
                dvDistance.innerHTML = "";
                dvDistance.innerHTML += "Distance: " + distance + "<br />";
                dvDistance.innerHTML += "Duration:" + duration;
            }
        });
    }

    setInterval(myURL, 2000);
    function myURL() {
        SetTextBox();
        GetRoute();
    }

    function SetTextBox() {
        $.ajax({
            type: "Post",
            url: "Default.aspx/GetValue",
            data: '{}',
            contentType: "application/Json; Charset=utf-8",
            dataType: "json",
            success: function (response) {
                $('#txtSource').val(response.d.Source);
                $('#txtDestination').val(response.d.Destination);
            },
            error: function (response) {
                alert(response.d);
            }
        });
    };
</script>

Code

C#

[System.Web.Services.WebMethod]
public static object GetValue()
{
    return new { Source = "Mahim, Mumbai, India", Destination = "Malad, Mumbai, India" };
}

VB.Net

<System.Web.Services.WebMethod>
Public Shared Function GetValue() As Object
    Return New With {Key _
        .Source = "Mahim, Mumbai, India", Key _
        .Destination = "Malad, Mumbai, India"
    }
End Function

Screenshot