js 作用域

var 作用域范围大,下面可以修改他 let 作用域范围下,下面不可以修改

function varTest() {
  var x = 1;
  if (true) {
    var x = 2;  // 同样的变量!    console.log(x); // 2  }
  console.log(x);  // 2}

function letTest() {
  let x = 1;
  if (true) {
    let x = 2;  // 不同的变量    console.log(x);  // 2  }
  console.log(x);  // 1}

定义对象

let params = {
                projNo : sessionStorage.getItem('bills_projNo'),
                billMonth : sessionStorage.getItem('bills_month'),
                billState:'02',
                pageNum : self.pageNum,
                pageSize : self.pageSize,
            }

定义函数

//账单查询列表
querypreBillList() {
            let self = this;
            let params = {
                projNo : sessionStorage.getItem('bills_projNo'),
                billMonth : sessionStorage.getItem('bills_month'),
                billState:'02',
                pageNum : self.pageNum,
                pageSize : self.pageSize,
            }
            self.$axios.get(api.queryBillDetailsList,{params:params})
            .then(res=>{
                if(res.data.code = "S00000"){
                    self.tableData = res.data.data.list;
                    self.pageNum = params.pageNum;
                    self.totalRows = Number(res.data.data.total);
                }
            }).catch((err) => {
                console.log(err);
            })
        },

设置message

// 新增客户联系人
addCustContactConfirm() {
        const vm = this;
        let api
        if (this.editType === "新增") {
          vm.addCustContactForm.coocustNo = this.$route.query.coocustNo;//this.$route.query.coocustNo;
          api = "addCrmCustAttn"
        } else {
          api = "modifyCocustLinkman"
        }
        vm.$axios.post(basicUrl+"/crmCustAttn/" + api,vm.addCustContactForm)
          .then(res => {

            if(res.data.code === "S00000") {
              this.$message({ message: res.data.retMsg, type: 'success' });
            }else {
              this.$message({ message: res.data.retMsg, type: 'error' });
            }

            this.getCustContactList()
          })
          .catch(err =>{
          })
        this.addCustContactVisible = false;
        //console.log(this.addCustContactForm);
      },