I am trying to create a form that will give an alert if a field is empty, or if the fields are not empty then it will take the user to a new page(this page does exist) I have tried replacing 'button' with 'input', but still no hope
<div id='signupbox'>
<div class="formbox">
<h1>My first contact form</h1>
<p style="color:red;">Anything With a * is required</p>
<br>
<form name="app-form" onsubmit="return validateForm()" method="post">
<input name="Fname" id='Fname' type="text" class="feedback-input" placeholder="Fname" />
<input name="Email" id='Email' type="text" class="feedback-input" placeholder="Email" />
<select name="languages" id="lang" class="feedback-input">
<option value="javascript">Select a language</option>
<option value="javascript">JavaScript</option>
<option value="php">PHP</option>
<option value="java">Java</option>
<option value="golang">Golang</option>
<option value="python">Python</option>
<option value="c#">C#</option>
<option value="C++">C++</option>
<option value="erlang">Erlang</option>
</select>
<textarea name="Text" id='Text' class="feedback-input" placeholder="Comment"></textarea>
<button type='submit' onclick="return validateFormData(); Link();" >SUBMIT</button>
</form>
</div>
</div>
</body>
<script>
function validateForm() {
let x = document.forms["app-form"]["Fname"].value;
let y = document.forms["app-form"]["Email"].value;
if ((x == "") || (y=='')) {
alert("Required Fields Must be Filled Out.");
return false;}}
function Link(){
document.location.href = "SuccessPage.html";
}
</script>
Also oninvalid attribute does give an alert if the case is to warn the user by showing an alert:
<input
name="Fname"
id='Fname'
type="text"
class="feedback-input"
oninvalid="alert('Required Fields Must be Filled Out.!');" placeholder="Fname" />
<input
name="Email"
id='Email'
type="text"
class="feedback-input"
oninvalid="alert('Required Fields Must be Filled Out.!');" placeholder="Email" />
Check HTML oninvalid Event Attribute for detailed information.
Your onClick method is wrong. It should be this:
<button type='submit' onclick="validateFormData()" >SUBMIT</button>
In your validateFormData method you should check to make sure the form has data, if it does then you call your Link() method. If it doesn't, display an alert.
firstly, if you want a good form page, you have to prevent default behaves like page renewing thus you can have so good form validating process. I edited your code please use this.
<div id='signupbox'>
<div class="formbox">
<h1>My first contact form</h1>
<p style="color:red;">Anything With a * is required</p>
<br>
<form name="app-form" method="post">
<input name="Fname" id='Fname' type="text" class="feedback-input" placeholder="Fname" />
<input name="Email" id='Email' type="text" class="feedback-input" placeholder="Email" />
<select name="languages" id="lang" class="feedback-input">
<option value="javascript">Select a language</option>
<option value="javascript">JavaScript</option>
<option value="php">PHP</option>
<option value="java">Java</option>
<option value="golang">Golang</option>
<option value="python">Python</option>
<option value="c#">C#</option>
<option value="C++">C++</option>
<option value="erlang">Erlang</option>
</select>
<textarea name="Text" id='Text' class="feedback-input" placeholder="Comment"></textarea>
<button type='submit' id="button" >SUBMIT</button>
</form>
</div>
</div>
</body>
<script>
document.getElementById("button").addEventListener("submit", function validateForm(e) {
e.preventDefault();
let x = document.getElementById("Fname").value;
let y = document.getElementById("Email").value;
if (!x || !y) {
alert("Please fill required areas.")
return
} else {
window.location.href="/SuccessPage.html"
}}
)
</script>