an Internet Explorer phenomanon

[phppup]

I have a basic <form action=insert.php>  I developed it and have it working well. It provides confirmation and error messages upon submission as designed.

When I visited a friend to show him the form, we used his Internet Explorer (not sure of the version) browser rather than the FIrefox that I had been used to.

Naturally, the look was slightly different, but upon submission, it went to the PHP page with a simple one word message of: undefined.

We used his laptop which had Chrome and all was well.

Is there a known issue or coding that I need to avoid such instances in real use situations?

 

[NotionCommotion]

You need to change <form action=insert.php> to <form action="insert.php">.  Evidently, FF automatically "fixes" your mistake, but you should always ensure your HTML is valid.  Use https://validator.w3.org/ to show errors until you have none.

[requinix]

"undefined" is a Javascript thing - it wouldn't have come from PHP...

[phppup]

I believe the quote marks are in the original scripting, just not included in the expedited question entry.

Also, I will double check, but I do not recall placing any JavaScript in my coding (as PHP was giving me enough troubles on its own... LOL).

Edited June 17, 2018 by phppup

[NotionCommotion]

You will want to rule out potential issues.  Use https://developer.mozilla.org/en-US/docs/Tools/Network_Monitor to see if the request is actually being made to your server.  If not, use JavaScript's console.log() to investigate.  If so, use PHP's syslog() to investigate.

[maxxd]

This is too vague to answer, I think - is the 'undefined' something you wrote in your code? Are you using third party libraries? Post your form and processing code and we'll take a look. My initial thought is that you're doing something like

if(isset($_POST['submit'])){
// process the form
}else{
   echo 'undefined';
}

(assuming the submit button is named 'submit') which won't work with Internet Explorer. But that's only my initial thought because it's something that has bitten a lot of developers.

Edited June 17, 2018 by maxxd
Clarification

[phppup]

Nope, I don't create messages that say things like "undefined."

My messages are more specific and fun (like echo "Time for lunch" which is always easy to find in a script).

[benanamen]

You will get much better help if you post your code.

[phppup]

KUDOS to requinix.

You were correct.  After closer review I realized that I had used a JavaScripted datepicker in my form and it was causing the quirky error.

After removing it, the error vanished.  Replaced it with a simple HTML <input type='date'> and seems to be okay.

GOOD CALL, thanks.