网页打开时Javascript第一次不工作

Question

我正在进行一个项目，需要将我的数据发送到表单的firebase。

链接-http://ietvit.com/hackoff/

Github回购链接-https://github.com/vivanks/hackoffproject

但在填写表单时，它应该弹出警报窗口并提交表单，但当我第一次打开网站时，它在刷新时什么都不做，而是开始完美工作，但不是第一次。任何原因或任何预防建议。

示例：

我第一次打开我的网站并填写订阅表，但它只是简单地刷新页面，而不是更新firebase和弹出警报窗口。

我的html表单-

<form class="contact100-form validate-form">
<div class="wrap-input100 m-b-10 validate-input" data-validate = "Name is required">
<input id="name" class="s2-txt1 placeholder0 input100" type="text" name="name" placeholder="Your Name">
<span class="focus-input100"></span>
</div>

<div class="wrap-input100 m-b-20 validate-input" data-validate = "Email is required: [e-mail]">
<input id="email" class="s2-txt1 placeholder0 input100" type="text" name="email" placeholder="Email Address">
<span class="focus-input100"></span>
</div>

<div class="w-full">
<p class="s2-txt3 p-t-18">
And don’t worry, we hate spam too! You can unsubcribe at anytime.
</p><br>
<button id="submitBtn" onclick="submitDetail()" name="submit" class="flex-c-m s2-txt2 size4 bg1 bor1 hov1 trans-04">
Submit
</button>

</div>
</form>

我的java脚本-

var nameText = document.getElementById("name");
var emailText = document.getElementById("email");
var submitBtn = document.getElementById("submitBtn");
const firebaseRef = firebase.database().ref();


function submitDetail(){
var nText = nameText.value;
var eText = emailText.value;

firebaseRef.push().set({
name : nText,
email : eText
});
window.alert("Subscribed Successfully")
}

Answer 1

<div class="wrap-input100 m-b-20 validate-input" data-validate = "Email is required: [e-mail]">
<input id="email" class="s2-txt1 placeholder0 input100" type="text" name="email" placeholder="Email Address">
<span class="focus-input100"></span>
</div>
<div class="w-full">
<p class="s2-txt3 p-t-18">
And don’t worry, we hate spam too! You can unsubcribe at anytime.
</p><br>
<button id="submitBtn" onclick="submitDetail(event)" type="submit" name="submit" class="flex-c-m s2-txt2 size4 bg1 bor1 hov1 trans-04">
Submit
</button>
</div>
</form>

并在js中防止重载：

function submitDetail(ev){
ev.preventDefault();
var nText = nameText.value;
var eText = emailText.value;
firebaseRef.push().set({
name : nText,
email : eText
});
window.alert("Subscribed Successfully")

}