js注册表单验证无效

Question

我正在为我的注册表格执行javascript表格验证。但是，即使我不符合js的条件，验证数据也会存储在数据库中。

我在堆栈溢出中查看了该问题的先前答案，但未获得预期的输出。

JavaScript代码：

function validateform() {
  var uname = document.myform.uname.value;
  var password = document.myform.password.value;
  var repassword = document.myform.repassword.value;
  var email = document.myform.email.value;
  var atposition = email.indexOf("@");
  var dotposition = email.lastIndexOf(".");
  if (atposition < 1 || dotposition < atposition + 2 || dotposition + 2 >= x.length) {
    alert("Please enter a valid e-mail address \n atpostion:" + atposition + "\n dotposition:" + dotposition);
    email.focus();
    return false;
  }
  if (uname == null || uname == "") {
    alert("Name can't be blank");
    uname.focus();
    return false;
  }
  if (password.length < 6) {
    alert("Password must be at least 6 characters long.");
    password.focus();
    return false;
  }
  if (password != repassword) {
    alert("password must be same!");
    repassword.focus();
    return false;
  }
  return true;
} 

HTML表单：

<form action="" method="post" name="myform"  onSubmit="return 
validateform()">
  <input type="text" placeholder="Username" name="uname" required>
  <br>
  <input type="email" placeholder="EmailID" name="email" required>
  <br>
  <input type="password" placeholder="Password" name="password" required>
  <br>
  <input type="password" placeholder="Re-Type Password" name="repassword" required>
  <br>
  <input type="date" name="date">
  <p>Gender:</p>
  <p><input type="radio" name="gender" value="male" checked>Male</p>
  <p><input type="radio" name="gender" value="female">Female</p>
  <input type="submit" name="submit" value="Sign up"> 
</form>

请帮助我纠正问题。