Your core problem is here: 

if (exists $colD{$valA}) {
    ...
elsif (! exists $colD{$valA}) {
    ...
}

[download]

Clearly, if exists $colD{$valA} is false, then its negation must be true: 

if (exists $colD{$valA}) {
    ...
else {
    ...
}

[download]

However, as you never set $colD{$valA}, the condition will always be false and the else block will only ever be entered.

There are lots of other issues with this code. Here's a non-exhaustive list in no particular order.

Let Perl tell you when you've done something wrong

Add use warnings; - right after use strict; is a good place. If you're having trouble understanding the messages, add use diagnostics; for more verbose messages. Relevant documentation: warnings and diagnostics. 

...
use strict;
use warnings;
use diagnostics;
...

[download]
Lay out your code in a consistent fashion

Your indentations appear almost totally arbitrary and your use of whitespace seems quite erratic. This makes reading your code difficult but it doesn't need to be. Please read: perlstyle.

Use more meaningful variable names

There's a number of places where some sort of naming convention would have helped you. For instance, you use three variables for worksheet objects: $sheet, $worksheet1 and $worksheet. Except where you declare and assign these, they don't convey a lot of meaning. Perhaps $sheet_in and $sheet_out would have been more informative. And yes, that is two new names for three existing variables: another bug in your code that I just found!

Use lexical variables for filehandles

Instead of open FILE ..., use something like open my $whatever_fh .... See open for a discussion of this.

Avoid pointless repetition of code

You have the identical statement my $valA = $sheet->{Cells}[$row][0]->{Val}; in both blocks of your if-else code. This would be better as: 

my $valA = $sheet->{Cells}[$row][0]->{Val};
if (exists $colD{$valA}) {
...

[download]

That should be enough for you to get your code working. If you need to ask further questions, please first read: How do I post a question effectively?

-- Ken

In reply to Re: struggling with spreadsheet::WriteExcel and writing columns by kcott
in thread struggling with spreadsheet::WriteExcel and writing columns by trickyq

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