diff --git a/trunk/research/players/js/srs.page.js b/trunk/research/players/js/srs.page.js
index 9e5d7ae95..0fd37b2ad 100755
--- a/trunk/research/players/js/srs.page.js
+++ b/trunk/research/players/js/srs.page.js
@@ -52,7 +52,10 @@ function user_extra_params(query, params) {
         ) {
             continue;
         }
-        queries.push(key + '=' + query[key]);
+
+        if (query[key]) {
+            queries.push(key + '=' + query[key]);
+        }
     }
 
     return queries;
@@ -68,12 +71,12 @@ function user_extra_params(query, params) {
 function build_default_rtmp_url() {
     var query = parse_query_string();
 
-    var schema = (query.schema == undefined)? "rtmp":query.schema;
-    var server = (query.server == undefined)? window.location.hostname:query.server;
-    var port = (query.port == undefined)? schema=="http"?80:1935:query.port;
-    var vhost = (query.vhost == undefined)? window.location.hostname:query.vhost;
-    var app = (query.app == undefined)? "live":query.app;
-    var stream = (query.stream == undefined)? "livestream":query.stream;
+    var schema = (!query.schema)? "rtmp":query.schema;
+    var server = (!query.server)? window.location.hostname:query.server;
+    var port = (!query.port)? schema=="http"?80:1935:query.port;
+    var vhost = (!query.vhost)? window.location.hostname:query.vhost;
+    var app = (!query.app)? "live":query.app;
+    var stream = (!query.stream)? "livestream":query.stream;
 
     var queries = [];
     if (server != vhost && vhost != "__defaultVhost__") {
@@ -92,12 +95,12 @@ function build_default_rtmp_url() {
 function build_default_publish_rtmp_url() {
     var query = parse_query_string();
 
-    var schema = (query.schema == undefined)? "rtmp":query.schema;
-    var server = (query.server == undefined)? window.location.hostname:query.server;
-    var port = (query.port == undefined)? schema=="http"?80:1935:query.port;
-    var vhost = (query.vhost == undefined)? window.location.hostname:query.vhost;
-    var app = (query.app == undefined)? "live":query.app;
-    var stream = (query.stream == undefined)? "demo":query.stream;
+    var schema = (!query.schema)? "rtmp":query.schema;
+    var server = (!query.server)? window.location.hostname:query.server;
+    var port = (!query.port)? schema=="http"?80:1935:query.port;
+    var vhost = (!query.vhost)? window.location.hostname:query.vhost;
+    var app = (!query.app)? "live":query.app;
+    var stream = (!query.stream)? "demo":query.stream;
 
     var queries = [];
     if (server != vhost && vhost != "__defaultVhost__") {
@@ -118,11 +121,11 @@ function build_default_publish_rtmp_url() {
 function build_default_bandwidth_rtmp_url() {
     var query = parse_query_string();
 
-    var server = (query.server == undefined)? window.location.hostname:query.server;
-    var port = (query.port == undefined)? 1935:query.port;
+    var server = (!query.server)? window.location.hostname:query.server;
+    var port = (!query.port)? 1935:query.port;
     var vhost = "bandcheck.srs.com";
-    var app = (query.app == undefined)? "app":query.app;
-    var key = (query.key == undefined)? "35c9b402c12a7246868752e2878f7e0e":query.key;
+    var app = (!query.app)? "app":query.app;
+    var key = (!query.key)? "35c9b402c12a7246868752e2878f7e0e":query.key;
 
     return "rtmp://" + server + ":" + port + "/" + app + "?key=" + key + "&vhost=" + vhost;
 }
@@ -146,11 +149,11 @@ function build_default_hls_url() {
         server = query.hls_vhost;
     }
     
-    var port = (query.hls_port == undefined)? window.location.port:query.hls_port;
-    var app = (query.app == undefined)? "live":query.app;
-    var stream = (query.stream == undefined)? "demo":query.stream;
+    var port = (!query.hls_port)? window.location.port:query.hls_port;
+    var app = (!query.app)? "live":query.app;
+    var stream = (!query.stream)? "demo":query.stream;
 
-    if (port == "" || port == null || port == undefined) {
+    if (!port) {
         port = 8080;
     }