The three main ways Ajax handles cross-domain in jquery

one, the way to handle cross-domain:

1. Agent

2.XHR2

The XMLHttpRequest Level2 (and XHR2) provided in HTML5 have already implemented cross-domain access. But Ie10 does not support the following

Just fill in the response header on the service side:

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Header ("access-control-allow-origin:*"); /* Asterisks indicate that all domains are acceptable, */Header ("Access-control-allow-methods:get,post");

3.jsonP

principle:

Ajax itself is not cross-domain,
Cross-domain is achieved by generating a script tag. Because the SRC attribute of the script tag is not a cross-domain limitation.

In fact, set the datatype: ' Jsonp ' after the $.ajax method and Ajax XMLHttpRequest have nothing to do with, instead of the JSONP protocol. JSONP is an unofficial protocol that allows the server-side integration of script tags back to the client to achieve cross-domain access through JavaScript callback.

The cross-domain notation for Ajax:

(the remainder of the notation is the same as the non-cross-domain):

Like what

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