SignalR 跨域解决方案全面

 //PersistentConnection Mode

            app.UseCors(CorsOptions.AllowAll);

            //PersistentConnection Mode
            app.MapSignalR<MyConnection>("/server", new ConnectionConfiguration()
            {
            });
            // 有关如何配置应用程序的详细信息，请访问 http://go.microsoft.com/fwlink/?LinkID=316888

            //Hub Mode
            app.MapSignalR("/lcc", new HubConfiguration());

 //PersistentConnection Mode
            app.MapSignalR<MyConnection>("/server", new ConnectionConfiguration()
            {
                EnableJSONP = true
            });
            // 有关如何配置应用程序的详细信息，请访问 http://go.microsoft.com/fwlink/?LinkID=316888

            //Hub Mode
            app.MapSignalR("/lcc", new HubConfiguration() { EnableJSONP = true });

// 建立对应server端Hub class的对象，请注意geffChat的第一个字母要改成小写
        var chat = $.connection.myHub;

        $.connection.hub.url = 'http://localhost:2001/lcc';

        //把connection打开
        $.connection.hub.start().done(function () {
            chat.server.hello();
        });

        // 定义client端的javascript function，供server端hub，通过dynamic的方式，调用所有Clients的javascript function
        chat.client.sendMessage = function (message) {
            //当server端调用sendMessage时，将server push的message数据，呈现在wholeMessage中
            $('#messages').append('<li>' + message + '</li>');
        };

        $("#broadcast").click(function () {
            chat.server.sendMessage($('#msg').val());
            $('#msg').val("");
        });
        $("#btnStop").click(function () {
            $.connection.hub.stop();
        });

  var connection = $.connection("http://localhost:2001/server");

        connection.received(function (data) {
            $('#messages').append('<li>' + data + '</li>');
        });

        connection.start();

        $("#broadcast").click(function () {
            connection.send($('#msg').val());
        });
        $("#btnStop").click(function () {
            connection.stop();
        });

 // 建立对应server端Hub class的对象，请注意geffChat的第一个字母要改成小写
        var chat = $.connection.myHub;

        $.connection.hub.url = 'http://localhost:16727/lcc';

        //把connection打开
        $.connection.hub.start({ jsonp: true }).done(function () {
            chat.server.hello();
        });

        // 定义client端的javascript function，供server端hub，通过dynamic的方式，调用所有Clients的javascript function
        chat.client.sendMessage = function (message) {
            //当server端调用sendMessage时，将server push的message数据，呈现在wholeMessage中
            $('#messages').append('<li>' + message + '</li>');
        };

        $("#broadcast").click(function () {
            chat.server.sendMessage($('#msg').val());
            $('#msg').val("");
        });
        $("#btnStop").click(function () {
            $.connection.hub.stop();
        });

 var connection = $.connection("http://localhost:16727/server");

        connection.received(function (data) {
            $('#messages').append('<li>' + data + '</li>');
        });

        connection.start({ jsonp: true });

        $("#broadcast").click(function () {
            connection.send($('#msg').val());
        });
        $("#btnStop").click(function () {
            connection.stop();
        });