没有给我指示

Question

我可能不明白它是如何工作的，但是如果我输入@Model.name ，它将找到一个地址（只是为了您的测试目的而编一个地址），以下javascript应该可以找到我，找到目的地并找到我的路线。

但事实并非如此。 为什么不呢？ 没有控制台错误。

    function success(position) {
    var s = document.querySelector('#status');

    if (s.className == 'success') {
        // not sure why we're hitting this twice in FF, I think it's to do with a cached result coming back    
        return;
    }

    s.innerHTML = "found you!";
    s.className = 'success';

    var mapcanvas = document.createElement('div');
    mapcanvas.id = 'mapcanvas';
    mapcanvas.style.height = '400px';
    mapcanvas.style.width = '560px';

    document.querySelector('article').appendChild(mapcanvas);

    var latlng = new google.maps.LatLng(position.coords.latitude, position.coords.longitude);
    var directionsService = new google.maps.DirectionsService();
    var directionsDisplay = new google.maps.DirectionsRenderer();

    var myOptions = {
        zoom: 15,
        center: latlng,
        mapTypeControl: false,
        navigationControlOptions: { style: google.maps.NavigationControlStyle.SMALL },
        mapTypeId: google.maps.MapTypeId.ROADMAP
    };

    var map = new google.maps.Map(document.getElementById("mapcanvas"), myOptions);

    var marker = new google.maps.Marker({
        position: latlng,
        map: map,
        title: "You are here! (at least within a " + position.coords.accuracy + " meter radius)"
    });

    var request = {
        origin: latlng,
        destination: '@Model.id',
        travelMode: google.maps.DirectionsTravelMode.DRIVING
    };

    directionsService.route(request, function (response, status) {
        if (status == google.maps.DirectionsStatus.OK) {
            directionsDisplay.setDirections(response);
        }
    });
}

function error(msg) {
    var s = document.querySelector('#status');
    s.innerHTML = typeof msg == 'string' ? msg : "failed";
    s.className = 'fail';

    // console.log(arguments);
}

if (navigator.geolocation) {
    navigator.geolocation.getCurrentPosition(success, error);
} else {
    error('not supported');
}

Answer 1

您必须为directionsDisplay定义map -option