从Chrome扩展程序的background.js获取响应

Question

I want to get cookie value from background js.Even though I am able to get cookie value in background but bot able to get cookie value in front js.

I want to just return value from background js to front.

front.js

$(document).on("click", ".darkbtn", function (event) {

      chrome.extension.sendRequest({ msg: "startFunc" },function(d){
          console.log(d);
      });
});

background.js

function getCookies(domain, name, callback) {

chrome.cookies.get({"url": domain, "name": name}, function(cookie) {
    if(callback) {
        callback(cookie.value);
    }
});
 }
 chrome.extension.onRequest.addListener(
 function(request, sender, sendResponse){
    if(request.msg == "startFunc") 
    {
        getCookies("http://localhost", "api_key", function(id) {
         //getCookies("http://developer.chrome.com/extensions/cookies.html", "Sample1", function(id) {
        sendResponse({data:id});
    });

                }
} 
 );

manifest.json permissions

"permissions": [
"tabs",
"storage",
"cookies",
"web_accessible_resources",
"<all_urls>"     
],

Answer 1

You may establish communication between extensions and their content scripts by using message passing . As detailed, since content scripts run in the context of a web page and not the extension, they often need some way of communicating with the rest of the extension.

Choose from different types of message passing as listed below depending on what you need:

1. Simple one-time requests

   If you only need to send a single message to another part of your extension (and optionally get a response back), you should use the simplified runtime.sendMessage or tabs.sendMessage .

2. Long-lived connections

   Sometimes it's useful to have a conversation that lasts longer than a single request and response. In this case, you can open a long-lived channel from your content script to an extension page, or vice versa, using runtime.connect or tabs.connect , respectively.

3. Cross-extension messaging

   In addition to sending messages between different components in your extension, you can use the messaging API to communicate with other extensions. This lets you expose a public API that other extensions can take advantage of.

Important information and examples on how to execute message passing are given in the documentation.