In this article I will explain with an example, how to perform Password and Confirm Password validation for Password TextBox using JavaScript in ASP.Net Core MVC.
The values of the Password and Confirm Password TextBoxes are compared using JavaScript and if the values do not match an error message is displayed.
The Controller consists of following Action method.
Action method for handling GET operation
Inside this Action method, simply View is returned.
public class HomeController : Controller
    public IActionResult Index()
        return View();
The View consists of two HTML Password TextBoxes and a Button.
The Button has been assigned a JavaScript OnClick event handler.
When the Submit Button is clicked, the Validate JavaScript function gets executed.
Inside the Validate JavaScript function, the values of the Password and the Confirm Password TextBoxes are fetched and are compared.
If the values do not match, an error message is displayed using JavaScript Alert Message Box.
    Layout = null;
<!DOCTYPE html>
    <meta name="viewport" content="width=device-width" />
            <td><input type="password" id="txtPassword" /></td>
            <td>Confirm Password:</td>
            <td><input type="password" id="txtConfirmPassword" /></td>
            <td><input type="button" id="btnSubmit" value="Submit" onclick="return Validate()" /></td>
    <script type="text/javascript">
        function Validate() {
            var password = document.getElementById("txtPassword").value;
            var confirmPassword = document.getElementById("txtConfirmPassword").value;
            if (password != confirmPassword) {
                alert("Passwords do not match.");
                return false;
            return true;
ASP.Net Core MVC: Password and Confirm Password validation using JavaScript
Browser Compatibility

The above code has been tested in the following browsers.

Internet Explorer  FireFox  Chrome  Safari  Opera 

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