一般情况下，一个网站中运行的javascript代码不能访问其他网站的资源.但是来自网站的 javascript 应该能够访问来自同一网站的资源.这称为 same-origin policy，并已实施所有主流浏览器(不仅仅是 Chrome).

也请阅读 https://developer.mozilla.org/en-US/docs/Same-origin_policy_for_file:_URIs 和 禁用同源策略铬 .

最快的解决方案是通过您的 localhost:8080 网站访问图像 - 然后，该网站中的 javascript 将能够访问同一网站中的图像资源.

I'm using leaflet-image.js to create an image from a leaflet map. The code used to create the image is the one in the example at https://github.com/mapbox/leaflet-image ie

var map = L.mapbox.map('map', 'YOUR.MAPID').setView([38.9, -77.03], 14);
leafletImage(map, function(err, canvas) {
    // now you have canvas
    // example thing to do with that canvas:
    var img = document.createElement('img');
    var dimensions = map.getSize();
    img.width = dimensions.x;
    img.height = dimensions.y;
    img.src = canvas.toDataURL();
    document.getElementById('images').innerHTML = '';
    document.getElementById('images').appendChild(img);
});

The problem is that the image seems to be blocked by some CORS security feature. Below is an image of the Google Chrome console (not that enevn in firefox it does not work)

Could you help me with that ? (Also all my server are locally hosted. Webserver, mapserver ...)

In general, javascript code running in a website cannot access resources from other websites. But a javascript from a website should be able to access resources from that same website. This is called same-origin policy, and is implemented by all major browsers (not just Chrome).

Do read also https://developer.mozilla.org/en-US/docs/Same-origin_policy_for_file:_URIs and Disable same origin policy in Chrome .

The quickest solution is to have the image reachable via your localhost:8080 website - then, the javascript in that website will be able to access a image resource in the same website.