You need to assign/push references to hashs/arrays, not the things themselves. 
my %tmpF=();
my @tmpA;
push(@tmpA,"0001");
%tmpF->{ID}=@tmpA;
push(@$fieldobj,%tmpF);

[download]

should be 

my %tmpF=();
my @tmpA;
push(@tmpA,"0001");
%tmpF->{ID}=\@tmpA;
#           ^
push(@$fieldobj,\%tmpF);
#               ^

[download]

Please read perlreftut to understand why you need references, and how they work.

In reply to Re: Arrays and Hashes woes by moritz
in thread Arrays and Hashes woes by TienLung

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