leave_form.html页面中点击立即申请按钮不生效

我的leave_form.html页面是照着视频敲的，但是为什么点击立即申请按钮不生效？代码全部替换成为源码包里的leave_form.html立即申请按钮点击后也仍然不生效？

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    <></>
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, methods:{
    changeTimeRange : function () {
        console.info(this.form.timeRange);
        this.form.startTime = this.form.timeRange[0].getTime();
        this.form.endTime = this.form.timeRange[1].getTime();
    },
    onSubmit(formName) {
        const objApp = this;
        const formData = this.form;
        const $message = this.$message;
        this.$refs[formName].validate(function (valid) {
            if (valid) {
                const params = new URLSearchParams();
                params.append("formType", formData.formType);
                params.append("startTime", formData.startTime);
                params.append("endTime", formData.endTime);
                params.append("reason", formData.reason);
                params.append("eid", sessionStorage.eid);
                axios.post("/api/leave/create", params)
                    .then(function (response){
                        console.info(response);
                        const json = response.data;
                        if (json.code == "0") {
                            objApp.$alert("请假单已提交，等待上级审批", {
                                callback:function () {
                                    window.location.href = "/notice.html";
                                }
                            })
                        }else {
                            $message.error({message:json.message,offset:100})
                        }
                    })
            }
        })
    }
}