fix: use mountedFieldsRef

Author: RylanBot

packages/components/form/Form.tsx

@@ -55,6 +55,8 @@ const Form = forwardRefWithStatics(
     const formRef = useRef<HTMLFormElement>(null);
     const formMapRef = useRef(new Map()); // 收集所有包含 name 属性 formItem 实例
     const floatingFormDataRef = useRef({}); // 储存游离值的 formData
+    const mountedFieldsRef = useRef<Set<string>>(new Set()); // Form 生命周期内所有曾经被 FormItem 挂载过的字段（fullPath 序列化后的字符串）
+
     const formInstance = useInstance(props, formRef, formMapRef, floatingFormDataRef, form);
 
     useImperativeHandle(ref, () => formInstance);
@@ -81,6 +83,7 @@ const Form = forwardRefWithStatics(
       form?.getInternalHooks?.(HOOK_MARK)?.notifyWatch?.([]);
       form.store = {};
       floatingFormDataRef.current = {};
+      mountedFieldsRef.current.clear();
       onReset?.({ e });
     }
 
@@ -115,6 +118,7 @@ const Form = forwardRefWithStatics(
           readOnly: props.readOnly || props.readonly,
           formMapRef,
           floatingFormDataRef,
+          mountedFieldsRef,
           onFormItemValueChange,
         }}
       >

packages/components/form/FormContext.tsx

@@ -23,6 +23,7 @@ const FormContext = React.createContext<{
   errorMessage: TdFormProps['errorMessage'];
   formMapRef: React.RefObject<Map<any, React.RefObject<FormItemInstance>>>;
   floatingFormDataRef: React.RefObject<Record<any, any>>;
+  mountedFieldsRef?: React.RefObject<Set<string>>;
   onFormItemValueChange: (changedValue: Record<string, unknown>) => void;
 }>({
   form: undefined,
@@ -44,6 +45,7 @@ const FormContext = React.createContext<{
   onFormItemValueChange: undefined,
   formMapRef: undefined,
   floatingFormDataRef: undefined,
+  mountedFieldsRef: undefined,
 });
 
 export const useFormContext = () => React.useContext(FormContext);

packages/components/form/FormItem.tsx

@@ -79,6 +79,7 @@ const FormItem = forwardRef<FormItemInstance, FormItemProps>((originalProps, ref
     statusIcon: statusIconFromContext,
     errorMessage,
     formMapRef,
+    mountedFieldsRef,
     onFormItemValueChange,
   } = useFormContext();
 
@@ -435,15 +436,25 @@ const FormItem = forwardRef<FormItemInstance, FormItemProps>((originalProps, ref
     shouldValidate.current = false;
     shouldEmitChangeRef.current = false;
 
-    // remount 场景
-    // 若 store 中已存在有效值，复用它并同步到本地 state
-    // 避免被 initialData / children 默认值抹回
-    const existingStoreValue = has(form?.store, fullPath) ? get(form?.store, fullPath) : undefined;
-    if (typeof existingStoreValue !== 'undefined') {
-      setFormValue(existingStoreValue);
+    // 区分「首次挂载」与「remount 到已有 form」：
+    //   - 首次挂载：mountedFieldsRef 中不含该 fullPath → 用 initialData 初始化 store
+    //   - remount：mountedFieldsRef 中已含该 fullPath → 保留 store 现值（可能是用户输入 / setFieldsValue 写入），
+    //     避免 Dialog / Popup 等场景下条件渲染引发 FormItem 卸载 → 重挂载时把已修改的字段恢复成 initialData
+    // FormItem 卸载不从 mountedFieldsRef 中移除，只有 Form 整体 reset 时才清空
+    const fieldKey = JSON.stringify(fullPath);
+    const isRemount = mountedFieldsRef?.current?.has(fieldKey) ?? false;
+    if (isRemount) {
+      const existingStoreValue = has(form?.store, fullPath) ? get(form?.store, fullPath) : undefined;
+      if (typeof existingStoreValue !== 'undefined') {
+        setFormValue(existingStoreValue);
+      } else {
+        set(form?.store, fullPath, defaultInitialData);
+        setFormValue(defaultInitialData);
+      }
     } else {
       set(form?.store, fullPath, defaultInitialData);
       setFormValue(defaultInitialData);
+      mountedFieldsRef?.current?.add(fieldKey);
     }
 
     return () => {

packages/components/form/_example/validate-complicated-data.tsx

@@ -121,7 +121,10 @@ export default function BaseForm() {
         theme="card"
         addable
         onAdd={onAddStudent}
-        style={{ marginLeft: 30, border: '1px solid var(--td-component-stroke)' }}
+        style={{
+          marginLeft: 30,
+          border: '1px solid var(--td-component-stroke)',
+        }}
       >
         {formData.students.map((student, index) => (
           <Tabs.TabPanel key={student.id} value={student.id} label={student.label} destroyOnHide={false}>
@@ -130,14 +133,19 @@ export default function BaseForm() {
                 <Input placeholder="请输入内容" />
               </FormItem>
 
-              <FormItem label="选科" name={`students[${index}].name`} label-width={80} initialData={student.courseType}>
+              <FormItem
+                label="选科"
+                name={`students[${index}].courseType`}
+                label-width={80}
+                initialData={student.courseType}
+              >
                 <Radio.Group>
                   <Radio value="wenke">文科</Radio>
                   <Radio value="like">理科</Radio>
                 </Radio.Group>
               </FormItem>
 
-              <FormItem label="课程" name={`students[${index}].name`} label-width={80} initialData={student.course}>
+              <FormItem label="课程" name={`students[${index}].course`} label-width={80} initialData={student.course}>
                 <Checkbox.Group>
                   {courseOptions.map(({ value, label }, index) => (
                     <Checkbox key={index} value={value} label={label} />