以下代码警告IE7中的ls exist
:
if(window.localStorage) {
alert('ls exists');
} else {
alert('ls does not exist');
}
IE7并不真正支持本地存储,但这仍然会提醒它。也许这是因为我在IE7浏览器中使用IE9并使用IE9开发人员工具进行文档模式。或者这可能是测试LS是否支持的错误方法。什么是正确的方法?
此外,我不想使用Modernizr,因为我只使用了一些HTML5功能,加载大型脚本不值得检测对这些内容的支持。
答案 0 :(得分:93)
您不必使用modernizr,但可以使用他们的方法来检测是否支持localStorage
modernizr at github
test for localStorage
// In FF4, if disabled, window.localStorage should === null.
// Normally, we could not test that directly and need to do a
// `('localStorage' in window) && ` test first because otherwise Firefox will
// throw bugzil.la/365772 if cookies are disabled
// Also in iOS5 & Safari Private Browsing mode, attempting to use localStorage.setItem
// will throw the exception:
// QUOTA_EXCEEDED_ERRROR DOM Exception 22.
// Peculiarly, getItem and removeItem calls do not throw.
// Because we are forced to try/catch this, we'll go aggressive.
// Just FWIW: IE8 Compat mode supports these features completely:
// www.quirksmode.org/dom/html5.html
// But IE8 doesn't support either with local files
Modernizr.addTest('localstorage', function() {
var mod = 'modernizr';
try {
localStorage.setItem(mod, mod);
localStorage.removeItem(mod);
return true;
} catch(e) {
return false;
}
});
使用当前源代码
进行了更新答案 1 :(得分:39)
if(typeof Storage !== "undefined")
{
// Yes! localStorage and sessionStorage support!
// Some code.....
}
else
{
// Sorry! No web storage support..
}
答案 2 :(得分:16)
此功能正常工作:
function supports_html5_storage(){
try {
return 'localStorage' in window && window['localStorage'] !== null;
} catch(e) {
return false;
}
}
答案 3 :(得分:15)
我也不想使用Modernizr,因为我只使用了几个HTML5 功能和加载一个大脚本是不值得的只是检测 支持这些事情。
要减少Modernizr文件大小,请在http://modernizr.com/download/自定义文件以满足您的需求。仅有localStorage版本的Modernizr的版本为1.55KB。
答案 4 :(得分:8)
尝试window.localStorage!==undefined
:
if(window.localStorage!==undefined){
//Do something
}else{
alert('Your browser is outdated!');
}
你也可以使用typeof window.localStorage!=="undefined"
,但上面的陈述已经做到了
答案 5 :(得分:7)
我没有在答案中看到它,但我认为很高兴知道你可以轻松地使用vanilla JS或jQuery进行这样简单的测试,而Modernizr帮助很多,有干净的没有它的解决方案。
如果您使用 jQuery ,则可以执行以下操作:
var _supportsLocalStorage = !!window.localStorage
&& $.isFunction(localStorage.getItem)
&& $.isFunction(localStorage.setItem)
&& $.isFunction(localStorage.removeItem);
或者,使用纯粹的Vanilla JavaScript :
var _supportsLocalStorage = !!window.localStorage
&& typeof localStorage.getItem === 'function'
&& typeof localStorage.setItem === 'function'
&& typeof localStorage.removeItem === 'function';
然后,您只需执行IF来测试支持:
if (_supportsLocalStorage) {
console.log('ls is supported');
alert('ls is supported');
}
因此,整个想法是,无论何时需要JavaScript功能,您都应首先测试父对象,然后测试代码使用的方法。
答案 6 :(得分:3)
尝试catch将完成这项工作:
try{
localStorage.setItem("name",name.value);
localStorage.setItem("post",post.value);
}
catch(e){
alert(e.message);
}
答案 7 :(得分:1)
尝试:
if(typeof window.localStorage != 'undefined') {
}
答案 8 :(得分:1)
if (window.localStorage){
alert('localStorage is supported');
window.localStorage.setItem("whatever", "string value");
}
答案 9 :(得分:0)
修改Andrea添加getter的答案使其更易于使用。如下所示,您只需说:if(ls)...
var ls = {
get: function () {
var test = 'test';
try {
localStorage.setItem(test, test);
localStorage.removeItem(test);
return true;
} catch(e) {
return false;
}
}
};
var ls = {
get: function () {
var test = 'test';
try {
localStorage.setItem(test, test);
localStorage.removeItem(test);
return true;
} catch(e) {
return false;
}
}
};
function script(){
if(ls){
alert('Yes');
} else {
alert('No');
}
}
<button onclick="script()">Local Storage Support?</button>
答案 10 :(得分:0)
我知道我参加聚会有点晚了,但是我整理了一些有用的功能,并将其放入名为“ manage_storage.js”的文件中。我希望它们对你们一样有用,因为它们为我提供了很好的服务。
记住:您要查找的功能(回答此问题)是
isLclStorageAllowed
。
因此,事不宜迟,这是我的代码:
/* Conditional Function checks a web browser for 'session storage' support. [BEGIN] */
if (typeof isSessStorageAllowed !== 'function')
{
function isSessStorageAllowed()
{
if (!!window.sessionStorage && typeof sessionStorage.getItem === 'function' && typeof sessionStorage.setItem === 'function' && typeof sessionStorage.removeItem === 'function')
{
try
{
var cur_dt = new Date();
var cur_tm = cur_dt.getTime();
var ss_test_itm_key = 'ss_test_itm_' + String(cur_tm);
var ss_test_val = 'ss_test_val_' + String(cur_tm);
sessionStorage.setItem(ss_test_itm_key, String(ss_test_val));
if (sessionStorage.getItem(ss_test_itm_key) == String(ss_test_val))
{
return true;
}
else
{
return false;
};
sessionStorage.removeItem(ss_test_itm_key);
}
catch (exception)
{
return false;
};
}
else
{
return false;
};
};
};
/* Conditional Function checks a web browser for 'session storage' support. [END] */
/* Conditional Function checks a web browser for 'local storage' support. [BEGIN] */
if (typeof isLclStorageAllowed !== 'function')
{
function isLclStorageAllowed()
{
if (!!window.localStorage && typeof localStorage.getItem === 'function' && typeof localStorage.setItem === 'function' && typeof localStorage.removeItem === 'function')
{
try
{
var cur_dt = new Date();
var cur_tm = cur_dt.getTime();
var ls_test_itm_key = 'ls_test_itm_' + String(cur_tm);
var ls_test_val = 'ls_test_val_' + String(cur_tm);
localStorage.setItem(ls_test_itm_key, String(ls_test_val));
if (localStorage.getItem(ls_test_itm_key) == String(ls_test_val))
{
return true;
}
else
{
return false;
};
localStorage.removeItem(ls_test_itm_key);
}
catch (exception)
{
return false;
};
}
else
{
return false;
};
};
};
/* Conditional Function checks a web browser for 'local storage' support. [END] */
/* Conditional Function checks a web browser for 'web storage' support. [BEGIN] */
/* Prerequisites: 'isSessStorageAllowed()', 'isLclStorageAllowed()' */
if (typeof isWebStorageAllowed !== 'function')
{
function isWebStorageAllowed()
{
if (isSessStorageAllowed() === true && isLclStorageAllowed() === true)
{
return true;
}
else
{
return false;
};
};
};
/* Conditional Function checks a web browser for 'web storage' support. [END] */