OpenLayers示例代码：地图导出
OpenLayers示例代码：地图导出
<!DOCTYPE html>
<html>
<head>
<title>Map Export</title>
<link rel="stylesheet" href="https://openlayers.org/en/v4.0.1/css/ol.css" type="text/css">
<!-- The line below is only needed for old environments like Internet Explorer and Android 4.x -->
<script src="https://cdn.polyfill.io/v2/polyfill.min.js?features=requestAnimationFrame,Element.prototype.classList,URL"></script>
<script src="https://openlayers.org/en/v4.0.1/build/ol.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/FileSaver.js/1.3.3/FileSaver.min.js"></script>
</head>
<body>
<div id="map" class="map"></div>
<a id="export-png" class="btn btn-default"><i class="fa fa-download"></i> Download PNG</a>
<script>
// this example uses FileSaver.js for which we don't have an externs file.
var map = new ol.Map({
layers: [
new ol.layer.Tile({
source: new ol.source.OSM()
}),
new ol.layer.Vector({
source: new ol.source.Vector({
url: 'https://openlayers.org/en/v4.0.1/examples/data/geojson/countries.geojson',
format: new ol.format.GeoJSON()
})
})
],
target: 'map',
controls: ol.control.defaults({
attributionOptions: /** @type {olx.control.AttributionOptions} */ ({
collapsible: false
})
}),
view: new ol.View({
center: [0, 0],
zoom: 2
})
});
document.getElementById('export-png').addEventListener('click', function() {
map.once('postcompose', function(event) {
var canvas = event.context.canvas;
if (navigator.msSaveBlob) {
navigator.msSaveBlob(canvas.msToBlob(), 'map.png');
} else {
canvas.toBlob(function(blob) {
saveAs(blob, 'map.png');
});
}
});
map.renderSync();
});
</script>
</body>
</html>
说明：
OpenLayers示例代码：地图导出
