报错has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.

解决：php后台 添加

header("ACCESS-CONTROL-ALLOW-ORIGIN:*");

还有一种情况用axios的 在请求的时候加

axios post的请求

methods: {
    onSubmit() {
      //提交
      let formarr = {
        name: this.form.name,
        sex: this.form.sex,
        date1: this.form.date1,
        sign: this.form.sign
      };
      axios({
        method: "post",
        url: "http://xxx.com/api/index/addUser",
        params: formarr,
        headers: {
          //fd:this.loginFrom.selectLimit, Content-Type: application/x-www-form-urlencoded
          "Content-Type": "application/x-www-form-urlencoded"
          //  Accept:'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8',
          //  Cookie:'SESSION=MDQ2N2QzN2UtNDU5OS00MDQ1LTk4ODAtNGNlZmJlZTYyZTQ3'
        }
        // withCredentials:true
      })
        .then(result => {
          console.log(result);
          if (result.data == 1) {
            //this.open2(); 成功提示
            this.$router.push({path:'/'}) //成功之后跳转
          }
        })
        .catch(error => {
          console.log(error);
        });
    },
   
  }

axios get的请求

  getData: function(pageNum,pageSize) {
        this.page.pageNum=pageNum ||  this.page.pageNum
        this.page.pageSize=pageSize        
        axios({
          method:'get',     
          url:"http://xxx.com/api/index/user",
           params:{
              pageNum:pageNum,
              limit:pageSize            
           },
          headers:{
             'Content-Type':'application/x-www-form-urlencoded',
          },
          
        }).then((result)=>{
            console.log(result.data)          
            this.tableData = result.data.data;
            this.page.total = result.data.count; // 总页数          
        }).catch((error)=>{
          console.log(error)
        })

    }