Javascript to clear a form field issue Options

[Lexx87]

CODE

else if ( document.flight_form.destination.value != "Paris" )
{

document.flight_form.destination.value += "Paris";
document.flight_form.departfrom.focus(); //as the field is filled for the user, the next field is selected for them
document.getElementById("error").innerHTML="We're sorry, due to problems beyond our control only flights to Paris are currently availiable.";
valid = false;    
}

That code, if the value of the text box 'destination' is not Paris, it puts Paris in the text box. Yet the way that works, if say "Spain" is in the text box, all it will do is append Paris to it so the box will have "SpainParis" inside it.

I want to remove any string in the box and then insert Paris in its place.

I've tried "document.flight_form.destination.reset(); the line before, but that either doesn't work as the interpreter doesn't process line by line (not sure how it works), or reset() is not the right thing to use..or...well that's where i'm stuck!

Any help would be amazing.

Alex

This post has been edited by Lexx87: Apr 5 2011, 01:02 PM

[Frederiek]

Change this:

CODE

document.flight_form.destination.value += "Paris";

to this:

CODE

document.flight_form.destination.value = "Paris";

[Brian Chandler]

Change this:

CODE

document.flight_form.destination.value += "Paris";

to this:

CODE

document.flight_form.destination.value = "Paris";

It seems to me this is not a helpful answer. Of course it helps the questioner, who mindlessly pastes your correction in, and disappears until the next question, but it does not _help_ in the long term unless you at least explain *why* the correction works.

[Christian J]

That code, if the value of the text box 'destination' is not Paris, it puts Paris in the text box.

Wouldn't it be more user-friendly to say "Only flight to Paris are available" on the page right from the start? You might add a READONLY attribute to the text field to prevent users from changing it.

It seems to me this is not a helpful answer. Of course it helps the questioner, who mindlessly pastes your correction in, and disappears until the next question, but it does not _help_ in the long term unless you at least explain *why* the correction works.

So why does it work?

[Brian Chandler]

I think you know what I mean. If people come here to be spoonfed with "Replace [string of gobbledygook] with [different string of gobbledygook] " they are not going to learn anything.

Does the OP understand what the javascript += operator means? Presumably not: it means "append". So if x is the string 'plip", then x += '-plop' appends -plop, giving x the value 'plip-plop'.

But as you say (and your answer seems to me vastly more constructive), this is all a barmy way to be doing things in the first place.