38 lines
1.2 KiB
JavaScript
38 lines
1.2 KiB
JavaScript
// browser shim for xmlhttprequest module
|
|
|
|
var hasCORS = require('has-cors');
|
|
|
|
module.exports = function (opts) {
|
|
var xdomain = opts.xdomain;
|
|
|
|
// scheme must be same when usign XDomainRequest
|
|
// http://blogs.msdn.com/b/ieinternals/archive/2010/05/13/xdomainrequest-restrictions-limitations-and-workarounds.aspx
|
|
var xscheme = opts.xscheme;
|
|
|
|
// XDomainRequest has a flow of not sending cookie, therefore it should be disabled as a default.
|
|
// https://github.com/Automattic/engine.io-client/pull/217
|
|
var enablesXDR = opts.enablesXDR;
|
|
|
|
// XMLHttpRequest can be disabled on IE
|
|
try {
|
|
if ('undefined' !== typeof XMLHttpRequest && (!xdomain || hasCORS)) {
|
|
return new XMLHttpRequest();
|
|
}
|
|
} catch (e) { }
|
|
|
|
// Use XDomainRequest for IE8 if enablesXDR is true
|
|
// because loading bar keeps flashing when using jsonp-polling
|
|
// https://github.com/yujiosaka/socke.io-ie8-loading-example
|
|
try {
|
|
if ('undefined' !== typeof XDomainRequest && !xscheme && enablesXDR) {
|
|
return new XDomainRequest();
|
|
}
|
|
} catch (e) { }
|
|
|
|
if (!xdomain) {
|
|
try {
|
|
return new global[['Active'].concat('Object').join('X')]('Microsoft.XMLHTTP');
|
|
} catch (e) { }
|
|
}
|
|
};
|