JS alert in PL/SQL on Update

Question

Hello there,
I'm trying to make one of my forms work a bit better by adding a javascript alert message to a conditional PL/SQL statement on the Update action of a submit button, rather than sending the user to an error page.
Here's the code that I'm currently using:
declare
l_ordr_date DATE;
l_ship_date DATE;
l_url VARCHAR2(250);
begin
l_ordr_date := p_session.get_value_as_DATE(
p_block_name => 'DEFAULT',
p_attribute_name => 'A_DATE_OF_ORDER');
l_ship_date := p_session.get_value_as_DATE(
p_block_name => 'DEFAULT',
p_attribute_name => 'A_DATE_SHIPPED');
if l_ship_date >= l_ordr_date then
     doUpdate;
     l_url := 'portal30.home';     
     portal30.wwa_app_module.set_target(l_url, 'CALL');
else
     l_url := 'POS.INVALID_SHIPDATE_DYN.show';
     portal30.wwa_app_module.set_target(l_url, 'CALL');
end if;
end;
Within the 'else' actions, I'd like to remove what I have and just have an alert window open to tell the user to fix the problem. I've tried to use the htp.p tag, but no luck.
Any help/suggestions would be greatly appreciated.
Thx!

Answer 1

Hi Joshua,
I do not think that you can put the javascript in the else section where you wish it to be as that is the code which will get executed at the server side ans therefore there will be no use of javascript there.
I will explain you how to use javascript in the form and then I'll explain you what I ment by "l_form variable" in my earlier code.
see there are two aspect of javascripting
1)
You should be able to write javascript into the form.For doing that what you can do is that write a simple javascript like this,
in the additional pl/sql block "before displaying the ...".
htp.p('
<script>
function myFunc()
alert("hello world");
</script>
2)You should bea ble to invoke this function based on some event say button click.For that yo uhave to include a call like this from the button (or any event for that matter).
myFunc();return;
Now second part for you question.
"I don't know what the "var l_form = ele.form;" is supposed to do nor do I know why you have 2 extra "}"s below that " ?
Those 2 } were a mistake as it was just a code to give u a feeling of how to put javascript in the form.The purpose of the var l_form =ele.form;
was to get the form object and then iterate along it to get the value of your text fields(or any element) from which you wish to get the values for comparsion.
Now after getting the form object what you have to do is something like this.
//this is your logical block for javascript.
var l_DATE_OF_ORDER;
var l_DATE_SHIPPED;
for (var i = 0; i < l_form.length ; i++){  //itereate trough all the elements.
if (l_form.elements.name == "<YOUR FORN NAME>.DEFAULT.A_DATE_OF_ORDER.01"){
l_DATE_OF_ORDER = l_form.elements[i].value;
if (l_form.elements[i].name == "<YOUR FORN NAME>.DEFAULT.A_DATE_SHIPPED.01"){
l_DATE_SHIPPED = l_form.elements[i].value;
//once you get both the values compare and get the control back into the
return;//do not submit the form and let the user fill the new date then if the condition is full fill then only let it be submitted for the update.
Please aply this as per your actual requirement.
Hope this helps.
rahul