修复直接修改表单项的值会清空其他项的值的bug

src/components/form/AdvancedForm.vue

@@ -15,7 +15,7 @@ const formData = computed(() => {
     props.formConfig?.formItems.forEach(item => {
       res.label = item.label
       item.group.forEach(element => {
-        res[element.name] = element.value
+        res[element.name] = res[element.name] && element.value !== undefined ? res[element.name] : element.value
       })
     })
     return res

src/components/form/BasicForm.vue

@@ -13,7 +13,7 @@ const formData = computed(() => {
   } else {
     const res = props.formData
     props.formConfig?.formItems.forEach(item => {
-      res[item.name] = item.value
+      res[item.name] = res[item.name] && item.value !== undefined ? res[item.name] : item.value
     })
     return res
   }

src/views/form/Basic.vue

@@ -40,13 +40,13 @@ const formConfig = reactive<BasicForm>({
     {
       label: '字段名',
       value: '',
-      name: 'name',
+      name: 'field1',
       type: 'input'
     },
     {
       label: '字段名',
       value: '',
-      name: 'name',
+      name: 'field2',
       type: 'input',
       slots: [
         {
@@ -62,7 +62,7 @@ const formConfig = reactive<BasicForm>({
     {
       label: '字段名',
       value: '',
-      name: 'field',
+      name: 'field3',
       type: 'cascader',
       props: {
         options: [