thymeleaf_form : th:object, th:field

thymeleaf_form/src/main/java/hello/itemservice/web/form/FormItemController.java

@@ -32,7 +32,8 @@ public class FormItemController {
     }
 
     @GetMapping("/add")
-    public String addForm() {
+    public String addForm(Model model) {
+        model.addAttribute("item", new Item());
         return "form/addForm";
     }
 

thymeleaf_form/src/main/resources/templates/form/addForm.html

@@ -18,18 +18,18 @@
         <h2>상품 등록 폼</h2>
     </div>
 
-    <form action="item.html" th:action method="post">
+    <form action="item.html" th:action th:object="${item}" method="post">
         <div>
             <label for="itemName">상품명</label>
-            <input type="text" id="itemName" name="itemName" class="form-control" placeholder="이름을 입력하세요">
+            <input type="text" id="itemName" th:field="*{itemName}" class="form-control" placeholder="이름을 입력하세요">
         </div>
         <div>
             <label for="price">가격</label>
-            <input type="text" id="price" name="price" class="form-control" placeholder="가격을 입력하세요">
+            <input type="text" id="price" th:field="*{price}" class="form-control" placeholder="가격을 입력하세요">
         </div>
         <div>
             <label for="quantity">수량</label>
-            <input type="text" id="quantity" name="quantity" class="form-control" placeholder="수량을 입력하세요">
+            <input type="text" id="quantity" th:field="*{quantity}" class="form-control" placeholder="수량을 입력하세요">
         </div>
 
         <hr class="my-4">

thymeleaf_form/src/main/resources/templates/form/editForm.html

@@ -18,22 +18,22 @@
         <h2>상품 수정 폼</h2>
     </div>
 
-    <form action="item.html" th:action method="post">
+    <form action="item.html" th:action th:object="${item}" method="post">
         <div>
             <label for="id">상품 ID</label>
-            <input type="text" id="id" name="id" class="form-control" value="1" th:value="${item.id}" readonly>
+            <input type="text" id="id" name="id" th:field="*{id}" class="form-control" th:value="${item.id}" readonly>
         </div>
         <div>
             <label for="itemName">상품명</label>
-            <input type="text" id="itemName" name="itemName" class="form-control" value="상품A" th:value="${item.itemName}">
+            <input type="text" id="itemName" class="form-control" th:field="*{itemName}">
         </div>
         <div>
             <label for="price">가격</label>
-            <input type="text" id="price" name="price" class="form-control" value="10000" th:value="${item.price}">
+            <input type="text" id="price" class="form-control" th:field="*{price}">
         </div>
         <div>
             <label for="quantity">수량</label>
-            <input type="text" id="quantity" name="quantity" class="form-control" value="10" th:value="${item.quantity}">
+            <input type="text" id="quantity" class="form-control" th:field="*{quantity}">
         </div>
 
         <hr class="my-4">