Question

我遵循了本教程：http://www.youtube.com/watch?v=qUjQrThw-ss

我使用xampp来测试它。

问题是该窗口不会弹出窗口。

这是我的代码：

HTML：

<!doctype html>
<html>
<head>
    <title>Html5 Drawing App!</title>
    <link rel="stylesheet" type="text/css" href="style.css">
</head>
<body style='margin: 0'>
    <div id="toolbar">
        <div id="rad">
            Radius <span id="radval">10</span>
            <div id="decRad" class="radcontrol">-</div>
            <div id="incRad" class="radcontrol">+</div>
        </div>
        <div id="colors">
        </div>
        <div id="save">
        Save
        </div>
    </div>
    <canvas id="canvas" style="display: block;">
        Sorry, Your Browser Is Unsupported. Switch To Another Browser
    </canvas>
    <script src="main.js"></script>
    <script src="radius.js"></script>
    <script src="colors.js"></script>
    <script src="save.js"></script>
</body>
</html>

save.js：

var saveButton = document.getElementById('save');

saveButton.addEventListener('click', saveImage);

function saveImage(){
    var data = canvas.toDataURL();

    var request = new XMLHttpRequest();

    request.onreadystatechange = function(){
        if(request.readyState == 4 && request.status = 200){
            //do our stuff
            var response = request.responseText;
            window.open(response, '_blank', 'location=0, menubar=0');
        }
    }

    request.open('POST', 'save.php', true);
    request.setRequestHeader('Content-type', 'application/x-ww-form-urlencoded');
    request.send('img='+data);


    //window.open(data, '_blank', 'location=0, menubar=0'); 
}

save.php：

<?php

$data = $_POST_['img'];

$data = str_replace('data:image/png;base64', '', $data);
$data = str_replace(' ', '+', $data);

$img = base64_decode($data);

$path = 'images/' . uniqid() . '.png';
if(file_put_contents($path, $img)){
    print $path;
}else{
    header("HTTP/1.1 500 Internal Server Error");
}

?>

为什么不突然冒出来？使用Google Chromes开发人员工具，我收到以下错误：

Uncaught ReferenceError: Invalid left-hand side in assignment save.js:11
POST http://localhost/draw/save.php 500 (Internal Server Error) save.js:20
3
Uncaught ReferenceError: Invalid left-hand side in assignment

请帮我解决这个问题。感谢

Answer 1

您在此行中省略了等号：

if(request.readyState == 4 && request.status = 200){
                                             ^   should be ==

Answer 2

尝试修复以下错误：

if(request.readyState == 4 && request.status = 200){
                                             Λ
                                             |___ ==

request.setRequestHeader('Content-type', 'application/x-ww-form-urlencoded');
                                                        Λ
                                                        |___ www

$data = $_POST_['img'];
           Λ
           |___ $_POST[...

窗口不会在AJAX中弹出

2 个答案: