Receiving message in C# from Chrome Extension through Native Messaging

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C#

chrome

I am trying to get active Tab Title as well as URL from Google Chrome. I have installed Chrome extension manually and created a console application for getting the active tab title and url.

First of all I have installed Chrome Extension which contains file like manifest.json, background.js and popup.html. Below is my code.

background.js

var port = chrome.runtime.connectNative('com.example.native');
  
function onActivate(activeInfo) 
{
     chrome.tabs.get(activeInfo.tabId, MyCurrentTab);
}   
function getUrl(title, url)
{
    var o = { title: title, url: url };
    try 
    {       
        port.postMessage(o);
    }
    catch(err)
    {

         port = chrome.runtime.connectNative('com.example.native');
         port.postMessage(o);
    }       
}

function MyCurrentTab(tab) 
{
     getUrl( tab.title, tab.url );
}

chrome.tabs.onActivated.addListener(onActivate);

manifest.json

{
"name": "watchURL",
"description": "Reading Active Chrome URL",
"version": "2.0",
"permissions": [
"tabs",
"nativeMessaging"
],
"background": {
"scripts": ["background.js"],
"persistent": false
},
"browser_action": {
"default_title": "The active url read",
"default_popup": "popup.html"

},
"manifest_version": 2
}


Then I have created the host native json file for native messaging. Below is the code.

{
"name": "com.example.native",
"description": "Native support for Chrome Extension",
"path": "ChromeExt.exe",
"type": "stdio",
"allowed_origins": [
"chrome-extension://xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/"
]
}


After that, I have created registry entry for native messaging with same name (com.example.native).

The code for C# console application is shown below,

private static string OpenStandardStreamIn()
{
    //// We need to read first 4 bytes for length information
    Stream stdin = Console.OpenStandardInput();
    int length = 0;
    byte[] bytes = new byte[4];
    stdin.Read(bytes, 0, 4);
    length = System.BitConverter.ToInt32(bytes, 0);

    string input = "";
    for (int i = 0; i < length; i++)
    {
        input += (char)stdin.ReadByte();
    }

    return input;
}

I have kept the native host json file and C# application .exe file under the system32 folder. But when I am going to open www.google.com or then www.yahoo.com at the chrome browser, nothing happens. I have also written code for a file dump inside that C# app but no luck.

I will publish my extension later on google store once it is manually done successfully.

Now my question is how I need to execute this console application and fetch the Title and URL from the Chrome Extension.

What I am supposed to do now? Please help me in this regard.

Any kind of help will be highly appreciated.