compdfkit(win) - 修复、交换 reason location

Demo/Examples/Compdfkit_Tools/DigitalSignature/FillDigitalSignatureControl/FillDigitalSignatureControl.xaml.cs

@@ -458,7 +458,7 @@ namespace Compdfkit_Tools.PDFControl
             {
                 if ((bool)ReasonChk.IsChecked)
                 {
-                    reason = PositionTbx.Text;
+                    reason = (ReasonCmb?.SelectedItem as ComboBoxItem)?.Content?.ToString();
                 }
                 else
                 {
@@ -467,7 +467,7 @@ namespace Compdfkit_Tools.PDFControl
 
                 if ((bool)PositionChk.IsChecked)
                 {
-                    location = (ReasonCmb?.SelectedItem as ComboBoxItem)?.Content?.ToString();
+                    location = PositionTbx.Text; 
                 }
                 else
                 {