Javascript 如何检查浏览器是否支持 HTML5 文件上传（FormData 对象）？
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How can I check if the browser support HTML5 file upload (FormData object)?
提问by laukok
How can I check if the browser support HTML5 file upload (FormData object)?
如何检查浏览器是否支持 HTML5 文件上传（FormData 对象）？
var fd = new FormData();
Following the answer from this post, but the code does not return correct answer about the browser,
按照这篇文章的答案，但代码没有返回关于浏览器的正确答案，
window.onload = function()
{
if (!!window.FileReader)
{
alert('supported');
}
else
{
alert('not supported');
}
}
Firefox - supported
Chrome - supported
Opera - supported
Safari - not supported
IE9 - not supported
But the correct browser support should be,
但正确的浏览器支持应该是，
Firefox - supported
Chrome - supported
Opera - not supported
Safari - supported
IE9 - not supported
I have tested the html 5 file upload on Operaand it is notworking for sure.
我已经在Opera上测试了 html 5 文件上传，但它确实无法正常工作。
I am sure that safarisupports html 5 file upload.
我确信safari支持 html 5 文件上传。
回答by webinista
Try if( window.FormData === undefined )or if( window.FormData !== undefined ).
尝试if( window.FormData === undefined )或if( window.FormData !== undefined )。
回答by Leon
From http://blog.new-bamboo.co.uk/2010/7/30/html5-powered-ajax-file-uploads
来自 http://blog.new-bamboo.co.uk/2010/7/30/html5-powered-ajax-file-uploads
function supportAjaxUploadProgressEvents() {
var xhr = new XMLHttpRequest();
return !! (xhr && ('upload' in xhr) && ('onprogress' in xhr.upload));
};
As FormData, the ability to send() one, and the upload property (and its onprogress event) are all part of XMLHttpRequest level 2, you can test for .upload to see if you've got a level 2. I don't have a Mac handy, but the function (sadly, but correctly) returns false for Opera 11.50 (and true for Firefox 4).
作为 FormData，send() 的能力和上传属性（及其 onprogress 事件）都是 XMLHttpRequest 级别 2 的一部分，您可以测试 .upload 以查看您是否达到了级别 2。我没有手边有 Mac，但该函数（遗憾但正确）在 Opera 11.50 中返回 false（对于 Firefox 4 返回 true）。
回答by Faraz Kelhini
function supportFormData() {
return !! window.FormData;
}
Source: https://www.new-bamboo.co.uk/blog/2012/01/10/ridiculously-simple-ajax-uploads-with-formdata/
来源：https: //www.new-bamboo.co.uk/blog/2012/01/10/ridiculously-simple-ajax-uploads-with-formdata/
回答by Wavy Davy
This is the one-liner I use to check if the browser supports FormData and upload progress, in jQuery:
这是我用来检查浏览器是否支持 FormData 和上传进度的单行代码，在 jQuery 中：
var xhr2 = !! ( window.FormData && ("upload" in ($.ajaxSettings.xhr()) );
回答by albanx
On Safari 5.1.7 , Firefox <6, Opera < 12.14 form data is suported but it is buggy.
在 Safari 5.1.7 上，支持 Firefox <6、Opera < 12.14 表单数据，但有问题。
Safari will return file size 0
Opera does not support append method of form data
firefox <6 does not work correctly
Safari 将返回文件大小 0
Opera 不支持表单数据的追加方法
firefox <6 不能正常工作
回答by Sujay
You could may be use the workaround provided by this library. https://github.com/francois2metz/html5-formdata
您可以使用此库提供的解决方法。 https://github.com/francois2metz/html5-formdata
回答by programmer guy
You need to check if the browser supports the HTML5 file API. I do that by checking if the FileReader function is set, if it's not set it means that the browser won't support the file API.
您需要检查浏览器是否支持 HTML5 文件 API。我通过检查 FileReader 函数是否已设置来做到这一点，如果未设置，则意味着浏览器将不支持文件 API。
// Check if window.fileReader exists to make sure the browser supports file uploads
if (typeof(window.FileReader) == 'undefined')
{
alert'Browser does not support HTML5 file uploads!');
}
