Perl oop链接数据库

写得好纠结，目前不知道哪里有问题，还在研究。。

package TDmodule;
use DBI;

sub new{
  $self={};
  $self->{username}=undef;
  $self->{password}=undef;
  $self->{host}=undef;
  $self->{database}=undef;
  $self->{connect_db}=[];
  $self->{select_db}=undef;
  bless $self;
  return $self;
}

sub username{
  my $self=shift;
  if(@_){
    $self->{username}=shift;
  }
  return $self->{username};
}

sub password{
  my $self=shift;
  if(@_){
    $self->{password}=shift;
  }
  return $self->{password};
}

sub host{
  my $self=shift;
  if(@_){
    $self->{host}=shift;
  }
  return $self->{host};
}

sub database{
  my $self=shift;
  if(@_){
    $self->{database}=shift;
  }
  return $self->{database};
}

sub connect_db{
  my $self=shift;
  @{$self->{connect_db}}=DBI->connect("DBI:mysql:database=$self->{database};host=$self->{host}","$self->{username}","$self->{password}") or die "No:$!\n";
  @{$self->{connect_db}}->prepare("select * from old_papar");
  @{$self->{connect_db}}->execute();
  return @{$self->{connect_db}};
}

sub select_db{
  my $self=shift;
  if(@_){
      $db=@{$self->{connect_db}};
      my $select=$db->prepare(@_);
      $select->execute();
      $self{select_db}=$select->fetchrow_hashref();
      @{$self->{connect_db}}->disconnect;
  }
  return $self{select_db};
}

1;