is it possible to convert a string to varbinary in PHP without using the SQL function

you can cast a string as a binary if you are using a recent enough version of PHP.

$binary = (binary)$string;

(binary) casting and b prefix forward support was added in PHP 5.2.1

php sql-server codeigniter

public static function str2bin($str) {   return '0x'.strtoupper(bin2hex($str));}

php sql-server codeigniter

You can also use the pack function

exampleconvert {326546, 4356345, 43646346, 366357547} to var-binary as Unsigned int

$_BIN=pack('I*', 326546, 4356345, 43646346, 366357547);

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