修复了默认时间的组件有显示但是提交值是空的问题

src/components/DatePicker/src/DatePicker.vue

@@ -46,11 +46,11 @@ const picker = computed(() => {
     watch(
         () => props.value,
         (val) => {
-        modelValue.value = dayjs(val || undefined);
+            modelValue.value = val ? dayjs(val || undefined) : '';
         },
         {
-        immediate: true,
-    },
+            immediate: true
+        }
     );
     const handleChange = (time) => {
         emit('update:value', time);