Error in v-on handler (Promise/async): "TypeError: Cannot read property 'data' of undefined" // undefined

Question

我正在尝试将数据从 v-text-field 推送到 json 文件。当我在 Postman 上尝试它时它起作用了所以我猜错误来自客户端

product.vue

<v-container>
   <v-row>
      <v-col>
         <v-text-field
            label="440"
            v-model="onetext"
            ></v-text-field>
         <v-text-field
            label="Card Type"
            v-model="twotext"
            ></v-text-field>
         <v-text-field
            label="Card Type"
            v-model="threetext"
            ></v-text-field>
         <v-text-field
            label="Card Type"
            v-model="fourtext"
            ></v-text-field>
         <v-text-field
            label="Card Type"
            v-model="fivetext"
            ></v-text-field>
         <v-text-field
            label="Card Type"
            v-model="sixtext"
            ></v-text-field>
         <v-text-field
            label="Card Type"
            v-model="seventext"
            ></v-text-field>
      </v-col>
   </v-row>
</v-container>
</v-card-text>
<v-card-actions>
   <v-spacer></v-spacer>
   <v-btn color="primary"  @click="dialog = false">Close</v-btn>
   <v-btn color="primary"  @click="create">Save</v-btn>
</v-card-actions>

import ProductService from '@/services/ProductService'
export default {
  components: {},
  data() {
    return {
      dialog: false,
      product: null,
      onetext: null,
      twotext: null,
      threetext: null,
      fourtext: null,
      fivetext: null,
      sixtext: null,
      seventext: null
    }
  },
  async mounted() {},
  methods: {
    async create() {
      try {
        await ProductService.create(this.onetext, this.twotext, this.threetext, this.fourtext, this.fivetext, this.sixtext, this.seventext)
      } catch (error) {
        this.error = error.response.data.message
      }
    }
  }
}

ProductService.js

export default {
    create(){
        return Api().post('/product', one, two, three, four, five, six, seven);
    }
}

产品路由器：

router.post("/", function(req, res){
    try{
        const fileName = path.resolve("server",'../product.json');
        const file = require(fileName);

        const product = {
            101: req.params.one,
            201: req.params.two,
            420: req.params.three,
            440: req.params.four,
            444: req.params.five,
            451: req.params.six,
            452: req.params.seven
        }

        fs.writeFile(fileName, JSON.stringify(product, null, 2), function(err){
            if (err){
                return console.log(err);
            }
            console.log("the file was saved");
            res.status(200).json(product);
        });
    } catch(err){
        res.status(500).json({
            message: "Error writing to file",
            error: err
        });
    }
})

ERR: Error in v-on handler (Promise/async): "TypeError: Cannot read property 'data' of undefined"

为什么我会收到这个错误，我可以做些什么来解决这个问题？

编辑：预期 product.json 文件

{
  "101": 1.9,
  "201": 2.18,
  "420": 4.1,
  "440": 9.2,
  "444": 11.16,
  "451": 122.12,
  "452": 11.9
}

Answer 1

解法：

您的 create 函数正在使用未传递的参数。将其更改为：

export default {
    create(one, two, three, four, five, six, seven){ // <-- add arguments
        return Api().post('/product', one, two, three, four, five, six, seven);
    }
}

改进：

简化一切：

1) 将所有表单模型数据移动到一个数据对象中formData:

return {
  // ...
  formData: {
    onetext: null,
    twotext: null,
    ...
  }
}

2) 在模板中，不要硬编码 v-text-field 的列表，而是使用 v-for 遍历 formData 对象：

<v-text-field v-for="(value, key) in formData" :key="key"
              label="Card Type" v-model="formData[key]"
></v-text-field>

3) 在create方法中传递formData对象而不是多个参数：

await ProductService.create(this.formData);

4) 将 ProductService.create、Api().post 和 router.post 更改为 use/pass 该对象：

create(formData){ // <-- Accepts an object now
    return Api().post('/product', formData); // <-- Passes the object
}

这是一个demo

Error in v-on handler (Promise/async): "TypeError: Cannot read property 'data' of undefined" // undefined

Error in v-on handler (Promise/async): "TypeError: Cannot read property 'data' of undefined" // undefined

node.js

vue.js

vue-component

vuejs2

v-for