how to format printing output in php

问题

I'm new to php and made a code that takes some information from a database and converts it into code128 barcode. Echoing it to the page is no problem:

$finalvar = '<p>'.bar128(stripcslashes($row['Flowers'])).'</p>';
echo $finalvar;

So far so good. I now want to print this barcode on a network printer and use this:

$port = "9100";
$host = "10.64.33.33";
$socket = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);

if ($socket === false) {
    echo "socket_create() failed, reason: " . socket_strerror(socket_last_error    ()) . "\n";
} else {
    echo "OK.\n";
}
$result = socket_connect($socket, $host, $port);
if ($result === false) {
    echo "socket_connect() failed.\nReason: ($result) " . socket_strerror    (socket_last_error($socket)) . "\n";
} else {
    echo "OK.\n";
}
socket_write($socket, $finalvar);
socket_close($socket);

The printing works perfectly but instead of printing the barcode like in the picture, the paper looks like this:

<p><table cellpadding=0 cellspacing=0><tr><td><div class="128"
style"border-"

I think this is probably more of a formatting thing, but I didn't find anything that worked. How can I print $finalvar like in the picture shown above?

回答1:

Google search for "render html to image" gives a few results, e.g. here. Looking at the readme, it seems pretty straight forward to convert your html into an image/pdf like so (assuming you installed it)

use Spatie\Browsershot\Browsershot;    

Browsershot::html($someHtml)->savePdf('example.pdf');

I am not familiar with using sockets and printing, but you should then be able to just read the file content via e.g.

file_get_contents('file.pdf')

and do what you did before.

回答2:

For anyone who wonders how I made it:

Most label printers support their own languages like ZPL (Zebra Programming language) or DPL (Datamax Programming language). You can just send a command to convert and print your variable. You don't even need to convert it into barcode, the printer does that for you. You will need to send 1 line of ZPL to your printer. ZPL is very easy and you can see that for yourself here. As you can see in the link I provided, you can create a barcode with only this command:

^XA^BY5,2,270^FO100,550^BC^FD$yourvariable^FS^XZ

In my case, I used this exact code above to print a simple barcode. This is how you implement this in PHP and send it to the printer:

 $variable = "ABC123"; //the variable you want to convert to barcode and print
    $print_data = ^XA^BY5,2,270^FO100,550^BC^FD$variable^FS^XZ; //this is the ZPL Code
     
    // Open a telnet connection to the printer, then push all the data into it.
    try
    {
        $fp=pfsockopen("10.64.57.51",9100); //IP of your printer and port
        fputs($fp,$print_data);
    echo "Job sent";
        fclose($fp);
    }
    catch (Exception $e)
    {
    echo "Job Failed";}

Note: The ZPL Code I provided is made for the size of my labels. You might need to change some X and Y numbers to fit yours. You can test this on the Website I provided.

来源：https://stackoverflow.com/questions/54402000/how-to-format-printing-output-in-php

标签

php

html

css

sockets

printing