bluemix sendgrid发送电子邮件

Question

我正在尝试使用sendGrid发送验证电子邮件。我已经尝试了一切，但它没有用。是否有人有使用sendgrid的经验，谁能告诉我我的代码中有什么错误？我故意将电子邮件字段留空，只是想知道代码中的错误

require 'vendor/autoload.php';
require 'lib/SendGrid.php';

if (isset($_REQUEST["email"])) {


    $name = $_POST['name'];
    $emailadr = $_POST['email'];
    $password = $_POST['password'];
    $role = $_POST['role']; 


$strsq0 = "INSERT INTO users (name, email, password, role) VALUES ('" . $name . "','" . $emailadr . "', SHA1('".$password."'), '" . $role . "');"; //query to insert new user
    if ($mysqli->query($strsq0)) {
        //header("Location: ../index.php");
    } else {
        echo "Cannot insert into the data table; check whether the table is created, or the database is active. "  . mysqli_error();
    }    


$sg_username = "";
$sg_password = "";


$sendgrid = new SendGrid( $sg_username, $sg_password );
$mail = new SendGrid\Email();


try {
    $mail->
    setFrom( "" )->
    addTo( "" )->
    setSubject( "This Is The Subject" )->
    setText( "Hello," )->
    setHtml( "" );

    $response = $sendgrid->send( $mail );

    if (!$response) {
        throw new Exception("Did not receive response.");
    } else if ($response->message && $response->message == "error") {
        throw new Exception("Received error: ".join(", ", $response->errors));
    } else {
        print_r($response);
    }
} catch ( Exception $e ) {
    var_export($e);
}

}