diff --git a/MainWindow.xaml.cs b/MainWindow.xaml.cs
index 7c2e156..753e694 100644
--- a/MainWindow.xaml.cs
+++ b/MainWindow.xaml.cs
@@ -109,7 +109,7 @@ namespace SUNLIGHT_CDKEY
             string a;
             string b, my, mm, md;
 
-            if (sn_id.Text.Length <6)
+            if (sn_id.Text.Length <6)//id字节长度大于6有效
             {
                 sn_id.BorderBrush = new SolidColorBrush(System.Windows.Media.Color.FromArgb(255, 255,0, 0));
                 return;