jQuery，ajax不会缓存_Jquery_Ajax_Browser Cache

jQuery，ajax不会缓存

jquery ajax

jQuery，ajax不会缓存,jquery,ajax,browser-cache,Jquery,Ajax,Browser Cache,为什么我的jqueryajax不支持这个特性您可以在第二个示例中看到，没有“If None Match”标题。但是为什么呢在这两个测试的浏览器中，我有50%的改变，有一个缓存将按F5，但在简单地重新打开页面点击链接它不会工作无工作jQuery示例 var xmlhttp; if (window.XMLHttpRequest) {// code for IE7+, Firefox, Chrome, Opera, Safari xmlhttp=new XMLHttpRequest();

为什么我的jqueryajax不支持这个特性

您可以在第二个示例中看到，没有“If None Match”标题。但是为什么呢

在这两个测试的浏览器中，我有50%的改变，有一个缓存将按F5，但在简单地重新打开页面点击链接它不会工作

无工作jQuery示例

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()
{
    if (xmlhttp.readyState==4 && xmlhttp.status==200)
    {
        console.log( xmlhttp.responseText );
    }
}
xmlhttp.open("GET","/energyManagerSensor/getCleanData/sensor_id/4?shrink_type=day&from=18.11.2011&to=23.02.2013",true);
xmlhttp.send();

$.ajax({
    url: "/energyManagerSensor/getCleanData/sensor_id/4?shrink_type=day&from=18.11.2011&to=23.02.2013",
    type: 'GET',
    dataType: "json",
    cache: true,
    ifModified: true,
    success: function(return_data) {
    console.log(return_data);
    }
});

请求头

Accept  text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Encoding gzip, deflate
Accept-Language de-DE,de;q=0.9,en-US;q=0.8,en;q=0.7,de-CH;q=0.6,fr-FR;q=0.5,fr;q=0.4,en-gb;q=0.3,sr-RS;q=0.2,sr;q=0.1
Cache-Control   max-age=0
Connection  keep-alive
Cookie  PHPSESSID=iie173rsc5bqggll6uhmg6m7i6
Host    sfportal3_hh_dev
If-Modified-Since   Tue, 12 Feb 2013 0:0:0 GMT
If-None-Match   4SdayF1321570800T1361574000
Referer http://sfportal3_hh_dev/energyManagerDisplay/view/display_id/1
User-Agent  Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:18.0) Gecko/20100101 Firefox/18.0 FirePHP/0.7.1
x-insight   activate

Accept  application/json, text/javascript, */*; q=0.01
Accept-Encoding gzip, deflate
Accept-Language de-DE,de;q=0.9,en-US;q=0.8,en;q=0.7,de-CH;q=0.6,fr-FR;q=0.5,fr;q=0.4,en-gb;q=0.3,sr-RS;q=0.2,sr;q=0.1
Connection  keep-alive
Cookie  PHPSESSID=iie173rsc5bqggll6uhmg6m7i6
Host    sfportal3_hh_dev
Referer http://sfportal3_hh_dev/energyManagerDisplay/view/display_id/1
User-Agent  Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:18.0) Gecko/20100101 Firefox/18.0 FirePHP/0.7.1
X-Requested-With    XMLHttpRequest
x-insight   activate

响应头

Cache-Control   max-age=3600
Connection  close
Date    Tue, 12 Feb 2013 06:16:23 GMT
Expires Thu, 19 Nov 1981 08:52:00 GMT
Server  Apache/2.2.22 (Ubuntu)

Cache-Control   max-age=3600
Connection  Keep-Alive
Content-Type    text/json
Date    Tue, 12 Feb 2013 06:18:41 GMT
Etag    5SdayF1321570800T1361574000
Expires Tue, 12 Feb 2013 07:02:18 GMT
Keep-Alive  timeout=5, max=74
Last-Modified   Tue, 12 Feb 2013 0:0:0 GMT
Server  Apache/2.2.22 (Ubuntu)
Transfer-Encoding   chunked
X-Powered-By    PHP/5.3.10-1ubuntu3

jQuery示例不起作用

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() { if (xmlhttp.readyState==4 && xmlhttp.status==200) { console.log( xmlhttp.responseText ); } } xmlhttp.open("GET","/energyManagerSensor/getCleanData/sensor_id/4?shrink_type=day&from=18.11.2011&to=23.02.2013",true); xmlhttp.send();

$.ajax({ url: "/energyManagerSensor/getCleanData/sensor_id/4?shrink_type=day&from=18.11.2011&to=23.02.2013", type: 'GET', dataType: "json", cache: true, ifModified: true, success: function(return_data) { console.log(return_data); } });
请求头

Accept text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8 Accept-Encoding gzip, deflate Accept-Language de-DE,de;q=0.9,en-US;q=0.8,en;q=0.7,de-CH;q=0.6,fr-FR;q=0.5,fr;q=0.4,en-gb;q=0.3,sr-RS;q=0.2,sr;q=0.1 Cache-Control max-age=0 Connection keep-alive Cookie PHPSESSID=iie173rsc5bqggll6uhmg6m7i6 Host sfportal3_hh_dev If-Modified-Since Tue, 12 Feb 2013 0:0:0 GMT If-None-Match 4SdayF1321570800T1361574000 Referer http://sfportal3_hh_dev/energyManagerDisplay/view/display_id/1 User-Agent Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:18.0) Gecko/20100101 Firefox/18.0 FirePHP/0.7.1 x-insight activate

Accept application/json, text/javascript, */*; q=0.01 Accept-Encoding gzip, deflate Accept-Language de-DE,de;q=0.9,en-US;q=0.8,en;q=0.7,de-CH;q=0.6,fr-FR;q=0.5,fr;q=0.4,en-gb;q=0.3,sr-RS;q=0.2,sr;q=0.1 Connection keep-alive Cookie PHPSESSID=iie173rsc5bqggll6uhmg6m7i6 Host sfportal3_hh_dev Referer http://sfportal3_hh_dev/energyManagerDisplay/view/display_id/1 User-Agent Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:18.0) Gecko/20100101 Firefox/18.0 FirePHP/0.7.1 X-Requested-With XMLHttpRequest x-insight activate
响应头

Cache-Control max-age=3600 Connection close Date Tue, 12 Feb 2013 06:16:23 GMT Expires Thu, 19 Nov 1981 08:52:00 GMT Server Apache/2.2.22 (Ubuntu)

Cache-Control max-age=3600 Connection Keep-Alive Content-Type text/json Date Tue, 12 Feb 2013 06:18:41 GMT Etag 5SdayF1321570800T1361574000 Expires Tue, 12 Feb 2013 07:02:18 GMT Keep-Alive timeout=5, max=74 Last-Modified Tue, 12 Feb 2013 0:0:0 GMT Server Apache/2.2.22 (Ubuntu) Transfer-Encoding chunked X-Powered-By PHP/5.3.10-1ubuntu3
测试环境

Firefox18.0.2

铬24.0

我发现了问题：
1.）上的“ifModified” 在我看来这是完全错误的。在阅读jQuery之后，我将删除以下句子：
“仅当自上次请求后响应已更改时，才允许请求成功。”
我会写下这样的话：如果“ifModified”为true，则将使用lastModified和etag头选项进行活动缓存
2.）我在PHP中遇到了一个问题
要求始终发送ETag，在304响应的情况下也是如此

<?php // Save performance use ETag system // @see http://en.wikipedia.org/wiki/HTTP_ETag $lastmod = gmdate('D, d M Y 0:0:0 \G\M\T', time()); $etag = $sensor_id . 'S' . $shrink_type . 'A' . $alarms . 'F' . $from . 'T' . $to . 'D' . date('Dmy'); $ifmod = isset($_SERVER['HTTP_IF_MODIFIED_SINCE']) ? $_SERVER['HTTP_IF_MODIFIED_SINCE'] == $lastmod : null; $iftag = isset($_SERVER['HTTP_IF_NONE_MATCH']) ? $_SERVER['HTTP_IF_NONE_MATCH'] == $etag : null; header_remove('Pragma'); header_remove('Cache-Control'); header('Expires: ' . gmdate('D, d M Y H:m:i \G\M\T', time() + 3600)); header('Cache-Control: max-age=3600'); header('Last-Modified: ' . $lastmod); header('ETag: ' . $etag); if (($ifmod || $iftag) && ($ifmod !== false && $iftag !== false)) { header('HTTP/1.0 304 Not Modified'); die(); }

你在测试哪个浏览器？我不明白。解决办法是什么？您最初不是有jquery问题吗？我的问题是jquery.ajax的“ifModified”文档。由于缺少对文档的了解，我更改了php代码。此选项必须为true才能强制jQuery使用提供的HTTP ETag头。非常感谢！对于错过它的人来说，关键是：如果您的服务器返回304，请记住在其上附加ETag，否则jQuery不会使用缓存响应。