Value comparison must return greater value returns no value 2

[bigblock454]

Hi All, I'm trying to write a very simple script that will compare 2 values and return the greater of the two in a PDF form. So far, nothing I try will return a value.

It is a sales commission worksheet, where MinCommDue is a manually entered value that may or may not be populated (but is for my testing).
AllComs is a hidden field that is the sum of 4 other fields.

I need to compare the values and place whichever is greater in a different field.

I am very inexperienced in JS, any help would be greatly appreciated.

Here is the script:

var a=this.getField("MinCommDue");
var b=this.getField("AllComs");
if ((a.value >= b.value)){
event.value = a
} else {
if ((a.value <= b.value)) {
event.value = b
}
}

 

[Ascalonian]

First question is: Is it always numbers in those fields?

 

[bigblock454]

Ideally yes, the MinCommDue field could be left blank however. Otherwise, there should never be anything but numeric data in those fields.

 

[Diancecht]

I'm not sure about the answer, but here are some checkpoints:

- GetField returns the correct field
- a.value and b.value contain the expected values
- event.value should be a or b and not a.value or b.value

Cheers,
Dian

 

[cLFlaVA]

assuming you're error checking and data cleaning to ensure you're receiving numeric values, what's wrong with the max() function?



*cLFlaVA
----------------------------
[tt]"quote goes here"[/tt]
[URL unfurl="true"]http://www.coryarthus.com/[/url]

 

[bigblock454]

Diancecht, that's how it is written, but still not returning any value. Should a.value & b.value be written as a & b in my fi and else statements?

cLFlaVA, because I am too inexperienced to know how Tell how and I'll try it!

 

[cLFlaVA]

have you tried it yourself yet? there are examples in the link i provided above. something like

[tt]event.value = Math.max( a, b );[/tt]

what is "event"? if you are referencing / handling an event firing, i don't believe "value" is a legitimate property.



*cLFlaVA
----------------------------
[tt]"quote goes here"[/tt]
[URL unfurl="true"]http://www.coryarthus.com/[/url]

 

[Ascalonian]

What about this? Just coming up with it real fast..

var a = parseFloat(document.getElementById("MinCommDue"));
var b = parseFloat(document.getElementById("AllComs"));

if(!isNaN(a) && !isNaN(b)) {
   event.value = Math.max(a, b);
}else {
    // One of these was not a number
    event.value = "0";
}

 

[bigblock454]

cLFlaVA, I'm not sure why "event" is used, it works well in Adobe, and I have changed my script to:

var a = this.getField("MinCommDue");
var b = this.getField("AllComs");
event.value = Math.max(a.value,b.value);

This seems to be working exactly as needed, thank you very much!

 

[bigblock454]

MikeyJudd, I'll run that one through too, just to see if it works!

 

[bigblock454]

MikeyJudd, tried that and no value was returned, maybe it has to do with scripting within Acrobat? As I said, very green on JS! The simple 3 line script works though The only odd thing is that despite the formatting of each field as numeric, 2 decimal places, the script adds up what the fields would be if there were 3 decimal places and then rounds up to the next digit, causing it to be a penny off, which I can live with!

 

[cLFlaVA]

mikeyjudd, you'd need a .value after your getElementById call.



*cLFlaVA
----------------------------
[tt]"quote goes here"[/tt]
[URL unfurl="true"]http://www.coryarthus.com/[/url]

 

[Ascalonian]

If any of these fields are entered by users, you should always take into account user error. So doing a safe guard to make sure they entered correct data is a good practice to have. Which is why I had you do that check )

 

[Ascalonian]

Haha, like I said I wrote it fast. You're right, you do need the ".value" on the getElementById call.

 

[Ascalonian]

var a = parseFloat(this.getField("MinCommDue").value);
var b = parseFloat(this.getField("AllComs").value);

if(!isNaN(a) && !isNaN(b)) {
   event.value = Math.max(a, b);
}else {
    // One of these was not a number
    event.value = "0";
}

 

[bigblock454]

MikeyJudd, I am unsure how I would "check" the value input. The data will be entered by a user who now fills in the form by hand. I think I understand that the NaN is checking that the input is numeric, am I on the right track? And NOW your script works!

Since both scripts work, and because I am so inexperienced, which script would be more prudent to utilize?

Thanks, Dawn!

 

[Ascalonian]

Yes, the "isNaN" checks to make sure the value was parsed correctly to a float.

As a little FYI, "NaN" means "Not a Number".

As for which script to use, that is up to you. I personally would recommend the check I do. You mentioned that the data is entered by hand and humans make mistakes. Trust me, seen my share.

You could even extend your code to inform the user they made a mistake, such as:

var a = parseFloat(this.getField("MinCommDue").value);
var b = parseFloat(this.getField("AllComs").value);

if(!isNaN(a) && !isNaN(b)) {
   event.value = Math.max(a, b);
}else {
    // One of these was not a number
    event.value = "0";

    //Alert the user they entered the wrong data. This is assuming 'a' is the user input field
    alert("Number entered is not a valid number: " + a);
}

 

[bigblock454]

MikeyJudd, excellent! Thanks again, I learn something new everytime I come here

Dawn

 

[bigblock454]

Uh-Oh, got a syntax error on that last line, do I need a { before the word "alert"? That cleared the syntax error. (I try to learn, not just copy & paste!)

 

[cLFlaVA]

no. make sure you don't have a line break on your comments. all comment text needs to be preceded by "//" or encapsulated by "/*" and "*/".



*cLFlaVA
----------------------------
[tt]"quote goes here"[/tt]
[URL unfurl="true"]http://www.coryarthus.com/[/url]