use utf8;
use Encode;
use URI::Escape;

$ = "n";

#从unicode得到utf8编码
$str = '%u6536';
$str =~ s/%u([0-9a-fA-F]{4})/pack("U",hex($1))/eg;
$str = encode( "utf8", $str );
print uc unpack( "H*", $str );

# 从unicode得到gb2312编码
$str = '%u6536';
$str =~ s/%u([0-9a-fA-F]{4})/pack("U",hex($1))/eg;
$str = encode( "gb2312", $str );
print uc unpack( "H*", $str );

# 从中文得到utf8编码
$str = "收";
print uri_escape($str);

# 从utf8编码得到中文
$utf8_str = uri_escape("收");
print uri_unescape($str);

# 从中文得到perl unicode
utf8::decode($str);
@chars = split //, $str;
foreach (@chars) {
    printf "%x ", ord($_);
}

# 从中文得到标准unicode
$a = "汉语";
$a = decode( "utf8", $a );
map { print "u", sprintf( "%x", $_ ) } unpack( "U*", $a );

# 从标准unicode得到中文
$str = '%u6536';
$str =~ s/%u([0-9a-fA-F]{4})/pack("U",hex($1))/eg;
$str = encode( "utf8", $str );
print $str;

# 从perl unicode得到中文
my $unicode = "x{505c}x{8f66}";
print encode( "utf8", $unicode );

use Encode;
$gb=decode("euc-cn","$gb");
$unicode=$dbh->quote($gb);
# to insert $unicode to MySQL unicode general_ci table.