G'day gayu_justin,

Firstly, this code is highly confusing and a potential source of errors:

my $check_ = "chck";
my $chck_ = "check";

[download]

Regarding the code generating the error, instead of:

foreach $usr( @
#print $usr . "\n";
#print $check_.$usr;
my $check_.$usr = $cgi->param("$chck_.$usr");
print $chck_.$usr;
}

[download]

I suspect you want something closer to this (untested):

for my $user_id (@userchecklist_id) {
    my $checkbox_name = "check_$user_id";
    my $checkbox_value = $cgi->param($checkbox_name);
    print "Checkbox name:  $checkbox_name\n";
    print "Checkbox value: $checkbox_value\n";
}

[download]

By using meaningful variable names and taking a little care when laying out your code, you'll improve readability and maintainability. Take a look at perlstyle for some tips on the latter.

As a final point, note how you've reused $usr: 

my $usr = $user->id;
...
foreach $usr( @userchecklist_id) {

[download]

This, again, is a potential source of errors. Consider what might happen if you wanted to use the $user->id version of $usr after the loop. By using my when you start the loop (as I did) you get a different variable (scoped to the loop) and avoid possible future problems. [In case you didn't know, for and foreach are synonymous so you can save yourself some typing (see perlsyn - Foreach Loops).]

-- Ken

In reply to Re: showing the error ,Can't modify concatenation (.) or string in scalar assignment by kcott
in thread showing the error ,Can't modify concatenation (.) or string in scalar assignment by gayu_justin

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