How to get variable value in mail header php

In PHP, you can access the value of a variable in the mail header using the headers function and the mail function. Here are a few ways to do it:

Method 1: Using the headers function

$headers = array(
    'From: '. $from_email,
    'To: '. $to_email,
    'Subject: '. $subject,
    'X-Variable: '. $variable_value
);

mail($to_email, $subject, $message, implode("\r\n", $headers));

In this example, $variable_value is the value of the variable you want to include in the mail header.

Method 2: Using the mail function with the extra_headers parameter

mail($to_email, $subject, $message, null, 'X-Variable: '. $variable_value);

In this example, the extra_headers parameter is used to specify the additional headers, including the value of the variable.

Method 3: Using a custom mail function

function send_email($to_email, $subject, $message, $headers) {
    $headers = array_merge(array(
        'From: '. $from_email,
        'To: '. $to_email,
        'Subject: '. $subject
    ), $headers);
    mail($to_email, $subject, $message, implode("\r\n", $headers));
}

$headers = array('X-Variable: '. $variable_value);
send_email($to_email, $subject, $message, $headers);

In this example, a custom send_email function is defined that takes an array of headers as a parameter. The array_merge function is used to combine the default headers with the custom headers, including the value of the variable.

In all cases, make sure to replace $from_email, $to_email, $subject, $message, and $variable_value with the actual values you want to use.