Class URLRequestHeader

In Adobe^® AIR^®, content in the application security sandbox(such as content installed with the AIR application) can use any request headers, without error. However, for content running in Adobe AIR that is in a different security sandbox, or for content running in Flash^® Player, using following request headers cause a runtime error to be thrown, and the restricted terms are not case-sensitive (for example, Get, get, and GET are each not allowed):

In Flash Player and in Adobe AIR content outside of the application security sandbox, the following request headers cannot be used, and the restricted terms are not case-sensitive(for example, Get, get, and GET are all not allowed). Also, hyphenated terms apply if an underscore character is used(for example, both Content-Length and Content_Length are not allowed):

Accept-Charset, Accept-Encoding, Accept-Ranges, Age, Allow, Allowed, Authorization, Charge-To, Connect, Connection, Content-Length, Content-Location, Content-Range, Cookie, Date, Delete, ETag, Expect, Get, Head, Host, If-Modified-Since, Keep-Alive, Last-Modified, Location, Max-Forwards, Options, Origin, Post, Proxy-Authenticate, Proxy-Authorization, Proxy-Connection, Public, Put, Range, Referer, Request-Range, Retry-After, Server, TE, Trace, Trailer, Transfer-Encoding, Upgrade, URI, User-Agent, Vary, Via, Warning, WWW-Authenticate, x-flash-version.

URLRequestHeader objects are restricted in length. If the cumulative length of a URLRequestHeader object(the length of the name property plus the value property) or an array of URLRequestHeader objects used in the URLRequest.requestHeaders property exceeds the acceptable length, an exception is thrown.

Content running in Adobe AIR sets the ACCEPT header to the following, unless you specify a setting for the ACCEPT header in the requestHeaders property of the URLRequest class: text/xml, application/xml, application/xhtml+xml, text/html;q=0.9, text/plain;q=0.8, image/png, application/x-shockwave-flash, video/mp4;q=0.9, flv-application/octet-stream;q=0.8, video/x-flv;q=0.7, audio/mp4, ~~/~~;q=0.5

Not all methods that accept URLRequest parameters support the requestHeaders property, consult the documentation for the method you are calling. For example, the FileReference.upload() and FileReference.download() methods do not support the URLRequest.requestHeaders property.

Due to browser limitations, custom HTTP request headers are only supported for POST requests, not for GET requests.