问尝试catch不适用于sse

EN

        try {
            var source = new EventSource("http://s10/server.php");
            console.log(source);
        } catch (e) {
            console.log("ADSfasfasfasdfasdfas" + e)
        }

        source.addEventListener('error', function(e) {
            if (source.readyState == 2) {
                connectionClosed();//to change some style
                console.log("Disconnected");
            }

        }, false);

        source.onerror = function(e) {
            if (source.readyState != 0) {
                connectionClosed();//to change some style
                console.log("Disconnected");
            }
        };
        source.onclose = function() {
            connectionClosed();//to change some style
            console.log('Connection closed');
        }