runtime.sendMessage() 编辑

Sends a single message to event listeners within your extension or a different extension.

If sending to your extension, omit the extensionId argument. The runtime.onMessage event will be fired in each page in your extension, except for the frame that called runtime.sendMessage.

If sending to a different extension, include the extensionId argument set to the other extension's ID. runtime.onMessageExternal will be fired in the other extension.

Extensions cannot send messages to content scripts using this method. To send messages to content scripts, use tabs.sendMessage.

    This is an asynchronous function that returns a Promise.

    You can also use a connection-based approach to exchange messages.

    Syntax

    var sending = browser.runtime.sendMessage(
      extensionId,             // optional string
      message,                 // any
      options                  // optional object
    )
    

    Parameters

    extensionIdOptional
    string. The ID of the extension to send the message to. Include this to send the message to a different extension. If the intended recipient has set an ID explicitly using the applications key in manifest.json, then extensionId should have that value. Otherwise it should have the ID that was generated for the intended recipient.
    If extensionId is omitted, the message will be sent to your own extension.
    message
    any. An object that can be structured clone serialized.
    optionsOptional
    object.
    includeTlsChannelIdOptional
    boolean. Whether the TLS channel ID will be passed into runtime.onMessageExternal for processes that are listening for the connection event.
    This option is only supported in Chromium-based browsers.

    Depending on the arguments it is given, this API is sometimes ambiguous. The following rules are used:

    • if one argument is given, it is the message to send, and the message will be sent internally.
    • if two arguments are given:
      • the arguments are interpreted as (message, options), and the message is sent internally, if the second argument is any of the following:
        1. a valid options object (meaning, it is an object which contains only the properties of options that the browser supports)
        2. null
        3. undefined
      • otherwise, the arguments are interpreted as (extensionId, message). The message will be sent to the extension identified by extensionId.
    • if three arguments are given, the arguments are interpreted as (extensionId, message, options). The message will be sent to the extension identified by extensionId.

    Note that before Firefox 55, the rules were different in the 2-argument case. Under the old rules, if the first argument was a string, it was treated as the extensionId, with the message as the second argument. This meant that if you called sendMessage() with arguments like ("my-message", {}), then it would send an empty message to the extension identified by "my-message". Under the new rules, with these arguments you would send the message "my-message" internally, with an empty options object.

    Return value

    A Promise. If the receiver sent a response, this will be fulfilled with the response as a JSON object. Otherwise it will be fulfilled with no arguments. If an error occurs while connecting to the extension, the promise will be rejected with an error message.

    Browser compatibility

    BCD tables only load in the browser

    Examples

    Here's a content script that sends a message to the background script when the user clicks the content window. The message payload is {greeting: "Greeting from the content script"}, and the sender also expects to get a response, which is handled in the handleResponse function:

    // content-script.js
    
    function handleResponse(message) {
      console.log(`Message from the background script:  ${message.response}`);
    }
    
    function handleError(error) {
      console.log(`Error: ${error}`);
    }
    
    function notifyBackgroundPage(e) {
      var sending = browser.runtime.sendMessage({
        greeting: "Greeting from the content script"
      });
      sending.then(handleResponse, handleError);
    }
    
    window.addEventListener("click", notifyBackgroundPage);

    The corresponding background script looks like this:

    // background-script.js
    
    function handleMessage(request, sender, sendResponse) {
      console.log("Message from the content script: " +
        request.greeting);
      sendResponse({response: "Response from background script"});
    }
    
    browser.runtime.onMessage.addListener(handleMessage);

    Example extensions

    Acknowledgements

    This API is based on Chromium's chrome.runtime API. This documentation is derived from runtime.json in the Chromium code.

    Microsoft Edge compatibility data is supplied by Microsoft Corporation and is included here under the Creative Commons Attribution 3.0 United States License.

    // Copyright 2015 The Chromium Authors. All rights reserved.
    //
    // Redistribution and use in source and binary forms, with or without
    // modification, are permitted provided that the following conditions are
    // met:
    //
    //    * Redistributions of source code must retain the above copyright
    // notice, this list of conditions and the following disclaimer.
    //    * Redistributions in binary form must reproduce the above
    // copyright notice, this list of conditions and the following disclaimer
    // in the documentation and/or other materials provided with the
    // distribution.
    //    * Neither the name of Google Inc. nor the names of its
    // contributors may be used to endorse or promote products derived from
    // this software without specific prior written permission.
    //
    // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
    // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
    // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
    // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
    // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
    // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
    // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
    // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
    // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
    // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
    // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
    

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