add logic and unit test for []string type in query params
diff --git a/params.go b/params.go
index 948783b..509a7c7 100644
--- a/params.go
+++ b/params.go
@@ -144,6 +144,13 @@
 						params.Add(tags[0], strconv.FormatInt(v.Int(), 10))
 					case reflect.Bool:
 						params.Add(tags[0], strconv.FormatBool(v.Bool()))
+					case reflect.Slice:
+						switch f.Type {
+						case reflect.TypeOf([]string{}):
+							for i := 0; i < v.Len(); i++ {
+								params.Add(tags[0], v.Index(i).String())
+							}
+						}
 					}
 				} else {
 					// Otherwise, the field is not set.