又是一個總是報的錯，出現在iview的級聯選擇器裏
[Vue warn]: Error in created hook: "TypeError: Cannot read property 'length' of null"
found in
---> <Cascader>
<FormItem>
<IForm>
<Index> at src/view/goods-manager/goods-manager.vue
<Content>
<Layout>
<Content>
<Layout>... (1 recursive calls)
<Main> at src/components/main/main.vue
<App> at src/App.vue
<Root>
warn @ webpack-internal:///./node_modules/[email protected]@vue/dist/vue.runtime.esm.js:602
webpack-internal:///./node_modules/[email protected]@vue/dist/vue.runtime.esm.js:1818 TypeError: Cannot read property 'length' of null
at deleteData (webpack-internal:///./node_modules/[email protected]@iview/dist/iview.js:9917)
at eval (webpack-internal:///./node_modules/[email protected]@iview/dist/iview.js:9920)
at Array.map (<anonymous>)
at deleteData (webpack-internal:///./node_modules/[email protected]@iview/dist/iview.js:9918)
at VueComponent.eval (webpack-internal:///./node_modules/[email protected]@iview/dist/iview.js:9928)
at Array.map (<anonymous>)
at VueComponent.getValidData (webpack-internal:///./node_modules/[email protected]@iview/dist/iview.js:9926)
at VueComponent.created (webpack-internal:///./node_modules/[email protected]@iview/dist/iview.js:9935)
at callHook (webpack-internal:///./node_modules/[email protected]@vue/dist/vue.runtime.esm.js:3024)
at VueComponent.Vue._init (webpack-internal:///./node_modules/[email protected]@vue/dist/vue.runtime.esm.js:4712)
logError @ webpack-internal:///./node_modules/[email protected]@vue/dist/vue.runtime.esm.js:1818
報這個錯，直接影響到我的級聯選擇器裏沒有值，非常奇怪。
猜測是children屬性undefined