Javascript正在提交一个简单的请求，但没有得到正确的反馈

Question

我有以下设置，其中Javascript发送一个AJAX请求并且它被执行得很好。问题是AJAX提交没有得到服务器的回复以显示在UI中。 console.log(msg)可以正常工作，但其余的都没有表现。如何确保在Javascript中收到PHP的每个输出？

ajax.php：

<?php
    $cmd = $_POST['command'];
    echo shell_exec("/usr/local/software/bin/cli -x '{$cmd}'");
?>

javascript.php：

$.post('ajax.php', {
    action: 'FEEDBACK-PLEASE?????',
    command: 'show status'
}, function(msg) {
    console.log(msg); // shows data arrived
    // following does not show the msg at all
    $('#terminal_output').html(msg); 
    alert('HELLO!!!!!! HELLO!! where is my feedback!! why you no alert???');
}, 'json');

编辑： XHR正文有数据

Answer 1

你没有从你的帖子请求中返回json删除json属性

$.post('ajax.php', {
    action: 'FEEDBACK-PLEASE?????',
    command: 'show status'
}, function(msg) {
    console.log(msg); // shows data arrived
    // following does not show the msg at all
    $('#terminal_output').html(msg); 
});