diff --git a/router.go b/router.go
index f556848b..54c60009 100644
--- a/router.go
+++ b/router.go
@@ -311,7 +311,6 @@ func (p *ControllerRegistor) ServeHTTP(rw http.ResponseWriter, r *http.Request)
 
 	params := make(map[string]string)
 
-	context.Input.Param = params
 	if p.enableFilter {
 		if l, ok := p.filters["BeforRouter"]; ok {
 			for _, filterR := range l {
@@ -412,6 +411,7 @@ func (p *ControllerRegistor) ServeHTTP(rw http.ResponseWriter, r *http.Request)
 			break
 		}
 	}
+	context.Input.Param = params
 
 	if runrouter != nil {
 		if r.Method == "POST" {
@@ -584,6 +584,14 @@ func (p *ControllerRegistor) ServeHTTP(rw http.ResponseWriter, r *http.Request)
 
 	if p.enableAuto {
 		if !findrouter {
+			lastindex := strings.LastIndex(requestPath, "/")
+			lastsub := requestPath[lastindex+1:]
+			if subindex := strings.LastIndex(lastsub, "."); subindex != -1 {
+				context.Input.Param[":ext"] = lastsub[subindex+1:]
+				r.URL.Query().Add(":ext", lastsub[subindex+1:])
+				r.URL.RawQuery = r.URL.Query().Encode()
+				requestPath = requestPath[:len(requestPath)-len(lastsub[subindex:])]
+			}
 			for cName, methodmap := range p.autoRouter {
 
 				if strings.ToLower(requestPath) == "/"+cName {
diff --git a/router_test.go b/router_test.go
index a79e5a4f..96800fb8 100644
--- a/router_test.go
+++ b/router_test.go
@@ -21,6 +21,10 @@ func (this *TestController) List() {
 	this.Ctx.Output.Body([]byte("i am list"))
 }
 
+func (this *TestController) Myext() {
+	this.Ctx.Output.Body([]byte(this.Ctx.Input.Params(":ext")))
+}
+
 func TestUserFunc(t *testing.T) {
 	r, _ := http.NewRequest("GET", "/api/list", nil)
 	w := httptest.NewRecorder()
@@ -45,6 +49,18 @@ func TestAutoFunc(t *testing.T) {
 	}
 }
 
+func TestAutoExtFunc(t *testing.T) {
+	r, _ := http.NewRequest("GET", "/test/myext.json", nil)
+	w := httptest.NewRecorder()
+
+	handler := NewControllerRegistor()
+	handler.AddAuto(&TestController{})
+	handler.ServeHTTP(w, r)
+	if w.Body.String() != "json" {
+		t.Errorf("user define func can't run")
+	}
+}
+
 func TestRouteOk(t *testing.T) {
 
 	r, _ := http.NewRequest("GET", "/person/anderson/thomas?learn=kungfu", nil)