diff --git a/tests/main/main.go b/tests/main/main.go
index 338ae86..5891abc 100644
--- a/tests/main/main.go
+++ b/tests/main/main.go
@@ -10,9 +10,11 @@ import (
 func main() {
 	cc := tests.NewTestConfig()
 	cc.Redis.RedisAddress = "127.0.0.1:6637"
-	if err := xconf.Parse(cc, xconf.WithFiles("c1.yaml"), xconf.WithDebug(false)); err != nil {
+	xx := xconf.New(xconf.WithFiles("c1.yaml"), xconf.WithDebug(false))
+	if err := xx.Parse(cc); err != nil {
 		panic(err)
 	}
 	fmt.Println("cc.RedisAsPointer.RedisAddress ", cc.RedisAsPointer.RedisAddress)
 	fmt.Println("cc.Redis.RedisAddress ", cc.Redis.RedisAddress)
+	xx.Usage()
 }
diff --git a/xconf.go b/xconf.go
index 7803a07..4d57040 100644
--- a/xconf.go
+++ b/xconf.go
@@ -414,16 +414,17 @@ func (x *XConf) Parse(valPtr interface{}) error {
 // Usage 打印usage信息
 func (x *XConf) Usage(valPtr ...interface{}) {
 	using := x.zeroValPtrForLayout
-	if len(valPtr) == 0 {
+	if len(valPtr) != 0 {
 		using = reflect.New(reflect.ValueOf(valPtr).Type().Elem()).Interface()
 	}
 	if using == nil {
-		x.cc.LogWarning("should parse first")
+		x.cc.LogWarning("Usage: should parse first")
 		return
 	}
 	lines, magic, err := x.usageLines(using)
 	if err != nil {
-		x.cc.LogWarning("got error:" + err.Error())
+		err = fmt.Errorf("Usage err: " + err.Error())
+		x.cc.LogWarning(err.Error())
 		return
 	}
 	fmt.Fprintln(os.Stderr, xutil.TableFormat(lines, magic))