How to Prevent Ctrl V and Ctrl C in a Specific Textarea Using JavaScript?

How to Prevent Ctrl V, Ctrl C in JavaScript

Copying and pasting can be convenient for users, but there are situations where you may need to restrict this behavior, such as preventing users from copying sensitive information or manipulating data in a specific field. JavaScript provides a simple solution to detect and prevent Ctrl V and Ctrl C key combinations.

To achieve this, use the following steps:

1. Detect Ctrl Key: Use the keydown event to track when the Ctrl key is pressed and set a flag (ctrlDown) to indicate its state.
2. Handle Key Combinations: Within the keydown event handler for the specific textarea you want to restrict pasting in, check if the Ctrl key is pressed (ctrlDown) and the key code matches V (86) or C (67). If a combination is detected, prevent default behavior by returning false.
3. Allow Pasting Outside Restricted Area: To ensure pasting remains enabled outside the restricted textarea, use the document as the event target in a separate keydown event handler and perform the desired action (in this case, logging the event).

Here's an example code snippet:

<code class="javascript">$(document).ready(function() {
    var ctrlDown = false,
        ctrlKey = 17,
        cmdKey = 91,
        vKey = 86,
        cKey = 67;

    $(document).keydown(function(e) {
        if (e.keyCode == ctrlKey || e.keyCode == cmdKey) ctrlDown = true;
    }).keyup(function(e) {
        if (e.keyCode == ctrlKey || e.keyCode == cmdKey) ctrlDown = false;
    });

    $(".no-copy-paste").keydown(function(e) {
        if (ctrlDown &amp;&amp; (e.keyCode == vKey || e.keyCode == cKey)) return false;
    });
    
    // Document Ctrl + C/V 
    $(document).keydown(function(e) {
        if (ctrlDown &amp;&amp; (e.keyCode == cKey)) console.log("Document catch Ctrl+C");
        if (ctrlDown &amp;&amp; (e.keyCode == vKey)) console.log("Document catch Ctrl+V");
    });
});</code>

With this code in place, users will not be able to paste content into the restricted textarea while Ctrl V is pressed. They can still type text or use other keyboard shortcuts as usual.

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