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javascriptperlpack

javascript Perl pack

First, I'll tell you I cannot speak English, but I want to try and get information of how to implement a Perl pack into Javascript to make a node.js module.

To do that, I would like to get more information about the Perl pack. In particular, the information I especially want to know "C, H *, N".

Also, if I could get more information on jspack, that would be wonderful.

Thank you in advance.

What I actually tried.

However, it didn't work.

日本語(Japan)

Solution

  • pack 'C', pack 'N' and pack 'H*' are used to create a sequence of bytes.

    my $bytes = pack('C', $uint8);

# Array of bytes
var bytes = [];
bytes.push(uint8);

# String of bytes
var bytes = "";
bytes += String.fromCharCode(uint8);


    my $bytes = pack('N', $uint32);

# Array of bytes
var bytes = [];
bytes.push((uint32 >> 24) & 0xFF);
bytes.push((uint32 >> 16) & 0xFF);
bytes.push((uint32 >>  8) & 0xFF);
bytes.push((uint32      ) & 0xFF);

# String of bytes
var bytes = "";
bytes += String.fromCharCode((uint32 >> 24) & 0xFF);
bytes += String.fromCharCode((uint32 >> 16) & 0xFF);
bytes += String.fromCharCode((uint32 >>  8) & 0xFF);
bytes += String.fromCharCode((uint32      ) & 0xFF);


    my $bytes = pack('H*', $hex_str);

# Array of bytes
function hexToBytes(hex) {
    var bytes = [];
    for (var c = 0; c < hex.length; c += 2)
       bytes.push(parseInt(hex.substr(c, 2), 16));

    return bytes;
}

# String of bytes
function hexToBytes(hex) {
    var bytes = "";
    for (var c = 0; c < hex.length; c += 2)
       bytes += String.fromCharCode(parseInt(hex.substr(c, 2), 16));

    return bytes;
}