Question

我正在使用messsage事件在浏览器窗口之间进行通信。主窗口发布到iframe，iframe与父进行通信。这个职位总是有效的。 php回声使用以下命令回复消息：

echo "<script>document.write(parent.postMessage(" . json_encode($status) . ", '*'))</script>";

有时会收到消息，有时则不然。我确信正在发送消息，因为我可以记录echo "<script>...之后发送的状态消息。可能导致这个问题的原因是什么？

简化的javascript：

// posts login info to an iframe which logs user in 
postToIframe(path, parameters, "post");

// wait for server's response
var foundMessage = false;
var messageFn = function (e) {
    if (typeof e.data.status !== "undefined"){
        _jsonStatus = e.data.status;
        foundMessage = true;
    }
    window.removeEventListener("message", messageFn);
    messageFn = undefined;
    if (!foundMessage){
        _jsonStatus = "Unknown Message: " + v(e.data);
    }
};
window.addEventListener("message", messageFn, false);
var timer = new Date().getTime();
var interval = setInterval(function() { 
    var timer2 = new Date().getTime();
    var done = true;
    var message;
    if (_jsonStatus.indexOf('Error') === 0){
        message = _jsonStatus;
        console.log(message);
        done = true;
    } else if (timer2 - timer > 5000){
        message = 'Timeout: Failed to get report data'
        console.log(message);
        if (_this.status){
            _this.status(message, "red");
        }       
        done = true;
        if (typeof messageFn !== undefined){
            window.removeEventListener("message", messageFn);
        }       
    } else if (_jsonStatus.substr(0, 7) == "Success"){
        done = true;
    } else {
        // continue to wait
        done = false;
    }
    if (done == true){
        clearInterval(interval);
    }
}, 1000)

简化的php：

if ($userid > 0){
    $status['status'] = "Success. You are logged in.";
} else {
    $status['status'] = 'Error: Login Failed';
}

echo "<script>document.write(parent.postMessage(" . json_encode($status) . ", '*'))</script>";

javascript addEventListener“message”有时不会在浏览器窗口中收到

0 个答案: