获取语​​法错误：JSON.parse：JSON 数据第 1 行第 1 列的意外字符

Question

I am working on a contact form and this error is stoping it from working... i might be overseeing something. The funny part is that my code works if i use XMLHttpRequest instead of Fetch..

When using Fetch if i don't request for a response it doesn't throw me any error but doesn't work either.. As you can see i am debugging the parameteres being passed, and they are ok.

handleSubmit(e) 
    {

        /*var xhr = new XMLHttpRequest();

        xhr.addEventListener('load', () => {console.log(xhr.responseText)});

        xhr.open('POST', 'http://localhost:3002/index.php');

        xhr.setRequestHeader("Content-Type", "application/json;charset=UTF-8");
        xhr.send(JSON.stringify(this.state));*/


        fetch('http://localhost:3002/index.php',
        {
            method: "POST",
            body: JSON.stringify(this.state),
            headers: {
                'Accept': 'application/json',
                'Content-Type': 'application/json'
            },
        }).then(
            console.log(JSON.stringify(this.state))
            ).then(
                (response) => (response.json())).then((response)=>
            {
                if (response.status === 'success')
                {
                    alert("Message Sent."); 
                    this.resetForm()
                }
                else if(response.status === 'fail')
                {
                    alert("Message failed to send.")
                }
            })

        e.preventDefault();

    }

And the response from php side:

...
                $sent = $mail->send();

                echo 'Message has been sent';

                if (isset($sent) && $sent === true) : ?> 
                {
                    "status": "success",
                    "message": "Your data was successfully submitted"
                }
                <?php endif;
            } 
            catch (Exception $e) 
            {
                echo "Message could not be sent. Mailer Error: {$mail->ErrorInfo}";
            }
        }
        else if (!empty($errors)) : ?> 
        {
            "status": "fail",
            "error":  <?php echo json_encode($errors) ?>
        }
        <?php endif;

Answer 1

    async function handleSubmit(e) {

    const response = await fetch("http://localhost:3002/index.php", {
        method: 'POST', // *GET, POST, PUT, DELETE, etc.
        cache: 'no-cache', // *default, no-cache, reload, force-cache, only-if-cached
        credentials: 'same-origin', // include, *same-origin, omit
        headers: {
            'Content-Type': 'application/json'
            // 'Content-Type': 'application/x-www-form-urlencoded',
        },
        body: JSON.stringify(this.state) // body data type must match "Content-Type" header
    });
    if (response.status === 'success')
    {
        alert("Message Sent.");
        this.resetForm()
    }
    else if(response.status === 'fail')
    {
        alert("Message failed to send.")
    }
    e.preventDefault();
}

Also have look at using_fetch