Display alert message in browser using Node.js

Question

I need to display an alert message in browser using Node.js code. Here my code

app.post('/logon', function (req, res)
   {
      var user=req.body.userName;
      var password=req.body.password;
      if((user=='admin')&&(password=='admin'))
         { 
              //redirect to home page
          }
       else
          {
                //here I need to display a alert message in browser saying that invalid user name or password is wrong
           }
       ..........

@FelixKling Is there any way to do that in server side like res.write or any other. — Jayanth
– Jayanth, Commented Jan 7, 2015 at 5:04
Well, you can send any response back to the client, but the actual alert call has to be executed on the client. — Felix Kling
– Felix Kling, Commented Jan 7, 2015 at 5:06
@FelixKling Fine. While I am using this code res.write(alert("Please enter correct user name and password."), it showing [ReferenceError: alert is not defined]. — Jayanth
– Jayanth, Commented Jan 7, 2015 at 5:10
Because alert doesn't exist in a Node environment. It's a function only defined in browsers. As I said, you have to call alert in a client side script. — Felix Kling
– Felix Kling, Commented Jan 7, 2015 at 5:32

surajck · Accepted Answer · 2015-01-07 06:49:57Z

8

If you're using ajax to send the user name and password to the node server, then you can do a

app.post('/logon', function (req, res)
{
  var user=req.body.userName;
  var password=req.body.password;
  if((user=='admin')&&(password=='admin'))
      //redirect to home page
  else
      res.send(500,'showAlert')

on the server and in the error function of the ajax on the client side, do

error: function(error){
          if(error.responseText == 'showAlert')
              alert("Please enter correct user name and password.")

Like Felix Kling pointed out, this needs to be executed on the client side.

answered Jan 7, 2015 at 6:49

surajck

1,1759 silver badges24 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Display alert message in browser using Node.js

1 Answer 1

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related