vue 判斷數據是否爲空

<template>
  <div>數據是否爲空</div>
</template>

<script>
export default {
  name: "Orders",
  data() {
    return {
      abj: {},
      arr: []
    };
  },
  created() {
    //判讀數組是否爲空
    if(this.arr == undefined || this.arr.length <= 0) {
      console.log("數組爲空");
    }
    if(this.arr !== undefined && this.arr.length > 0) {
      console.log("數組不爲空");
    }

    //判斷對象是否爲空
    if(JSON.stringify(this.obj) === "{}"){
      console.log("對象爲空");
    } else {
      console.log("對象不爲空");
    }
  },
  methods: {},
};
</script>

<style lang="scss" scoped></style>

1.數組爲空

this.arr == undefined || this.arr.length <= 0

2.數組不爲空

this.arr !== undefined && this.arr.length > 0

3.對象判斷

JSON.stringify(this.obj) === "{}"