Question

我正在努力清除地图中的所有折线，我只清楚最新的。

var polylines;

// add map polylines
function addPolyline(polyArray, colour) {
    polylines = L.polyline(polyArray, {color: colour});
    polylines.addTo(map);
}

// clear polylines   
function clearPolylines() {
    map.removeLayer(polylines);
}

其中addPolylines被多次调用，而clear Polylines被调用一次。如何清除地图上的所有折线？

Answer 1

你必须记住它们或者作弊并偷看map._layers才能找到它们。

EDIT通过@Ben添加示例代码：

function clearMap() {
    for(i in m._layers) {
        if(m._layers[i]._path != undefined) {
            try {
                m.removeLayer(m._layers[i]);
            }
            catch(e) {
                console.log("problem with " + e + m._layers[i]);
            }
        }
    }
}

Answer 2

您可以将折线添加到layerGroup，并轻松地将其添加到地图或从地图中删除。像这样：

pLineGroup = L.layerGroup()
var latlngs = [
    [45.51, -122.68],
    [37.77, -122.43],
    [34.04, -118.2]
];
this.pLineGroup.addLayer(L.polyline(latlngs, {color: 'red'}))
pLineGroup.addTo(map)
pLineGroup.removeFrom(map)

Answer 3

以下内容将删除多边形和标记，但将图像切片保留在背景中：

for (i in map._layers) {
    if (map._layers[i].options.format == undefined) {
        try {
            map.removeLayer(map._layers[i]);
        } catch (e) {
            console.log("problem with " + e + map._layers[i]);
        }
    }
}

Answer 4

您可以创建一个数组来存储地图中存在的所有折线。

var polylines = [];

创建每条折线时，我们将其添加到数组中：

var polyline = new L.Polyline(latlongs, {
    color: 'red',
    opacity: 1,
    weight: 1,
    clickable: false
}).addTo(map);
polylines.push(polyline);

现在，当我们需要从地图上清除多段线时，我们可以这样做：

polylines.forEach(function (item) {
    map.removeLayer(item)
});

Answer 5

一些答案建议使用 datetime64[ns]，它应该是一个 today_date = pd.to_datetime(dt.date.today()) final_df['Age'] = today_date - final_df["Contact Birth Date"] 属性，不应使用。最好使用 <form method="POST" class="rsvp-form js-form" id="rsvp-form" action="php/rsvp.php"> <div class="d-md-flex justify-content-between"> <div class="rsvp-form__left"> <div class="rsvp-form-field"> <input type="text" name="fullname" placeholder="Full Name" required> </div> <div class="rsvp-form-field"> <input type="email" name="email" placeholder="Your E-mail" class="js-email" required /> </div> <div class="rsvp-form-field"> <input type="text" name="guests" placeholder="Will you be bringing a plus one?" required> </div> <div class="rsvp-form-field"> <select name="attending" required tabindex="1"> <option value="" disabled selected>When we say 'I do', will we be seeing you?</option> <option value="Yes, wouldn't miss it for the world!"></option> <option value="No, will celebrate from afar!"></option> <option value="ceremony">Ceremony</option> <option value="party">Dinner & Party</option> </select> </div> </div> <div class="rsvp-form__right"> <div class="rsvp-form-field h-100"> <textarea rows="4" placeholder="Your Message" class="h-100" name="message"></textarea> </div> </div> </div> <button type="submit" class="rsvp-form-submit js-submit"> <span>Send</span> </button> </form> 类型的 API。

此外，您会发现如果 int 没有附加层，# Trying to make it have a special character when file is printed such as "$" Example: $2600 savings = '$' + input("How much money do you have in your savings: ") deposits = '$' + input("How much money do you put in deposits: ") 会崩溃，因为 map._layers 将是 private。

我想提出以下方法，它也会跳过您的归因：

L.Map

从传单地图中清除所有折线

5 个答案: