谁能告诉我如何从此$ http标头中删除预检请求

Question

    //individual logins
    $rootScope.setting.instances.forEach(function(ins) {

        var header = { 
                    "Accept": "application/json",
                    "Authorization": "Basic " + btoa( ins.uname + ':' + ins.pword ),
                    "Access-Control-Allow-Origin" : "*",
                    "Access-Control-Allow-Methods" : "GET, POST, DELETE, PUT, JSONP"

                };      

         $http({ method : 'post', url : ins.url, headers: header })
         .success( function( data )
         {
            console.log( ins.name +" login success" );
            $("#fail" + ins.id ).hide();
            $("#succ" + ins.id ).show();
            //logins : a global variable declared in app.js
            logins.push('{"ins" : '+ ins.id + ',"isAvailable" : "true"}');
            checkFinished();
         })
         .error( function( data)
         {
            console.log( ins.name +" login failed" );
            $("#fail" + ins.id ).show();
            $("#succ" + ins.id ).hide();
            //logins : a global variable declared in app.js
            logins.push('{"ins" : '+ ins.id + ',"isAvailable" : "false"}');
            checkFinished();
         });
    });
}

Answer 1

The CORS specification requires a browser to preflight the request with the OPTIONS request if any custom headers are specified on the cross origin request. And, when it does the OPTIONS preflight, it does not include your custom headers because part of what the OPTIONS request is for is to find out what custom headers are allowed to be sent on the request. So, a server is not supposed to require custom headers on the OPTIONS request if it wants this to work from a browser.

So, if you don't want it to preflight with the OPTIONS request, then you have to not use custom headers on the request.