How to get Clipboard data in Chrome Extension?

Basically you can manipulate clipboard using document.execCommand('paste|copy|cut').

• You'll need to specify "clipboardWrite" and/or "clipboardRead" permissions in manifest.

  "clipboardRead" Required if the extension or app uses document.execCommand('paste').

  "clipboardWrite" Indicates the extension or app uses document.execCommand('copy') or document.execCommand('cut'). This permission is required for hosted apps; it's recommended for extensions and packaged apps.

• Create <input> element (or <textarea>)

• Put focus to it
• Call document.execCommand('paste')
• Grab you string from <input> value attribute.

This worked for me to copy data to clipboard.

In order to read Clipboard text in a chrome extension, you have to:

• request "clipboardRead" permission in your manifest
• create a background script, since only the background script can access the clipboard
• create an element in your background page to accept the clipboard paste action. If you make this a textarea, you will get plain-text, if you make it a div with contentEditable=true, you will get Formatted HTML
• if you want to pass the clipboard data back to an in page script, you'll need to use the message-passing API

To see an example of this all working, see my BBCodePaste extension:

https://github.com/jeske/BBCodePaste

Here is one example of how to read the clipboard text in the background page:

bg = chrome.extension.getBackgroundPage();        // get the background pagebg.document.body.innerHTML= "";                   // clear the background page// add a DIV, contentEditable=true, to accept the paste actionvar helperdiv = bg.document.createElement("div");document.body.appendChild(helperdiv);helperdiv.contentEditable = true;// focus the helper div's contentvar range = document.createRange();range.selectNode(helperdiv);window.getSelection().removeAllRanges();window.getSelection().addRange(range);helperdiv.focus();    // trigger the paste actionbg.document.execCommand("Paste");// read the clipboard contents from the helperdivvar clipboardContents = helperdiv.innerHTML;

Here is a very simple solution. All it requires is for your permissions to include "clipboardRead" and "clipboardWrite". The copyTextToClipboard function is taken from here: https://stackoverflow.com/a/18455088/4204557

var t = document.createElement("input");document.body.appendChild(t);t.focus();document.execCommand("paste");var clipboardText = t.value; //this is your clipboard datacopyTextToClipboard("Hi" + clipboardText); //prepends "Hi" to the clipboard textdocument.body.removeChild(t);

Note that document.execCommand("paste") is disabled in Chrome, and will only work in a Chrome extension, not in a web page.