PHPMailer::replaceCustomHeader( string $name, string|null $value = null ): bool

4371    public function replaceCustomHeader($name, $value = null)4372    {4373        if (null === $value && strpos($name, ':') !== false) {4374            //Value passed in as name:value4375            list($name, $value) = explode(':', $name, 2);4376        }4377        $name = trim($name);4378        $value = (null === $value) ? '' : trim($value);4379 4380        $replaced = false;4381        foreach ($this->CustomHeader as $k => $pair) {4382            if ($pair[0] == $name) {4383                if ($replaced) {4384                    unset($this->CustomHeader[$k]);4385                    continue;4386                }4387                if (strpbrk($name . $value, "\r\n") !== false) {4388                    if ($this->exceptions) {4389                        throw new Exception(self::lang('invalid_header'));4390                    }4391 4392                    return false;4393                }4394                $this->CustomHeader[$k] = [$name, $value];4395                $replaced = true;4396            }4397        }4398 4399        return true;4400    }