always consider empty strings as no value given

components/App.tsx

@@ -11,10 +11,23 @@ import { IDocProps } from '../interfaces/IDocProps'
 
 export default function App() {
   const [options, setOptions] = useState<IDocProps>({
+    address: 'Max Mustermann\\\\Musterstrasse\\\\12345 Musterstadt',
+    body: 'Inhalt des Briefs',
+    closing: 'Mit freundlichen Grüßen',
+    customer: '',
+    date: new Date().toLocaleDateString('de-DE'),
+    enclosing: '',
+    invoice: '',
+    myRef: '',
+    opening: 'Sehr geehrte Damen und Herren',
+    ps: '',
+    signature: '',
+    specialMail: '',
+    subject: 'Betreffzeile',
     template: 'brief-fam',
-    subject: '',
-    body: '',
-    address: '',
+    yourMail: '',
+    yourRef: '',
+    yourRefName: '',
   })
   const [latest, setLatest] = useState<ILatest[]>([])
   const [pdfUrl, setPdfUrl] = useState<string | null>(null)
@@ -32,7 +45,7 @@ export default function App() {
       return
     }
     const value = event && event.target && event.target.value
-    setOptions({ ...options, [name]: value || undefined })
+    setOptions({ ...options, [name]: value })
   }
 
   const _onSelectLatest = (selectedOption: ILatest) => {