背景：我想创建一个可以随意改变外形的混合应用程序。这需要应用程序嵌入 webView。这个 webView 也应该能够与后端服务器对话。我使用非常小的 php 代码在我的 Mac (localhost) 上托管后端。
API
<?php
function getStatusCodeMessage($status)
{
// these could be stored in a .ini file and loaded
// via parse_ini_file()... however, this will suffice
// for an example
$codes = Array(
100 => 'Continue',
101 => 'Switching Protocols',
200 => 'OK',
201 => 'Created',
202 => 'Accepted',
203 => 'Non-Authoritative Information',
204 => 'No Content',
205 => 'Reset Content',
206 => 'Partial Content',
300 => 'Multiple Choices',
301 => 'Moved Permanently',
302 => 'Found',
303 => 'See Other',
304 => 'Not Modified',
305 => 'Use Proxy',
306 => '(Unused)',
307 => 'Temporary Redirect',
400 => 'Bad Request',
401 => 'Unauthorized',
402 => 'Payment Required',
403 => 'Forbidden',
404 => 'Not Found',
405 => 'Method Not Allowed',
406 => 'Not Acceptable',
407 => 'Proxy Authentication Required',
408 => 'Request Timeout',
409 => 'Conflict',
410 => 'Gone',
411 => 'Length Required',
412 => 'Precondition Failed',
413 => 'Request Entity Too Large',
414 => 'Request-URI Too Long',
415 => 'Unsupported Media Type',
416 => 'Requested Range Not Satisfiable',
417 => 'Expectation Failed',
500 => 'Internal Server Error',
501 => 'Not Implemented',
502 => 'Bad Gateway',
503 => 'Service Unavailable',
504 => 'Gateway Timeout',
505 => 'HTTP Version Not Supported'
);
return (isset($codes[$status])) ? $codes[$status] : '';
}
// Helper method to send a HTTP response code/message
// function sendResponse($status = 200, $body = '')
function sendResponse($status = 200, $body = '', $content_type = 'text/html')
{
$status_header = 'HTTP/1.1 ' . $status . ' ' . getStatusCodeMessage($status);
header($status_header);
header('Content-type: ' . $content_type);
echo $body;
}
class testPostApi {
function __construct() {
}
function __destruct() {
}
// Helper method to get a string description for an HTTP status code
// From http://www.gen-x-design.com/archives/create-a-rest-api-with-php/
// Main method to redeem a code
function testPost(){
// check for required parameters
if (isset($_POST["name"]) && isset($_POST["age"])){
$name = $_POST["name"];
$age = $_POST["age"];
// Return code, encoded with JSON
$result = array(
"name" => $name,
"age" => $age
);
sendResponse(200, json_encode($result));
return true;
}
sendResponse(400, 'Invalid request');
return false;
}
}
// This is the first thing that gets called when this page is loaded
// Creates a new instance of the RedeemAPI class and calls the redeem method
$api = new testPostApi;
$api->testPost();
?>
然后在 iOS 模拟器上运行一个小的 HTML5 脚本
<!DOCTYPE HTML>
<html>
<head>
<meta name="viewport" content="initial-scale=1, user-scalable=no">
</head>
<body>
<button onclick="submit()">Submit</button>
<script>
function submit()
{
var xmlhttp;
if (window.XMLHttpRequest)
{// code for IE7+, Firefox, Chrome, Opera, Safari
xmlhttp=new XMLHttpRequest();
}
else
{// code for IE6, IE5
xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange=function()
{
alert(xmlhttp.status);
/*if (xmlhttp.readyState==4 && xmlhttp.status==200)
{
}*/
}
var params = "name=john&age=40";
xmlhttp.open("POST","http://localhost/testPost",true);
xmlhttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xmlhttp.setRequestHeader("Content-length", params.length);
xmlhttp.setRequestHeader("Connection", "close");
xmlhttp.send(params);
}
</script>
</body>
</html>
问题：我使用终端命令测试curl -F "name=john" -F "age=40" http://localhost/testPost/并返回{"name":"john","age":"40"}。从而证明后端工作正常。但是当我使用模拟器按钮时，警报会显示代码 400（或未设置帖子值时我想要的任何内容）错误请求（状态 2、3、4 的 3 次）。
附加信息：使用 html 文件时，chrome 和 firefox 都返回代码 0。奇怪的是，Safari 实际上提供了与 iPhone 模拟器相同的代码。
问题：我在 AJAX/HTML5 代码中做错了什么？