异常捕获问题

老师好，发送请求时需要用catch捕获异常吗？为什么我看课程中有时候捕获，有时候不捕获？

                         axios.post("/api/member/registe" , params)
                            .then(function(response){
                                const json = response.data;
                                if(json.code == "0"){
                                    console.info(json);
                                    vant.Dialog.alert({
                                        title: "会员注册成功",
                                        message : "确定后跳转至登录页面"
                                    }).then(function(){
                                        window.location.href = "/login.html";
                                    })
                                }else {
                                    console.error(json);
                                    objApp.reloadVerifyCode();
                                    vant.Dialog.alert({
                                        title : "会员注册失败",
                                        message: json.message
                                    })
                                }
                            })