Update README.md (#136)

Ensure quantity is a number in ReadMe example, defaulting to 0 if undefined
notrab · Jul 10, 2024 · be94bd5 · be94bd5
1 parent 492e979
commit be94bd5
Showing 1 changed file with 2 additions and 2 deletions.
diff --git a/README.md b/README.md
@@ -103,12 +103,12 @@ function Cart() {
           <li key={item.id}>
             {item.quantity} x {item.name} &mdash;
             <button
-              onClick={() => updateItemQuantity(item.id, item.quantity - 1)}
+              onClick={() => updateItemQuantity(item.id, (item.quantity ?? 0) - 1)}
             >
               -
             </button>
             <button
-              onClick={() => updateItemQuantity(item.id, item.quantity + 1)}
+              onClick={() => updateItemQuantity(item.id, (item.quantity ?? 0) + 1)}
             >
               +
             </button>