Submit not calling JavaScript function

Question

Upon clicking submit, the function doesn't seem to get called and the form submits even if the return is false.

 function validateForm() {
 if (document.getElementById("nm").value="") {
 alert("You must enter a name!"); 
 return false;
 }
 if (document.getElementById("em").value="") {
 alert("email required"); 
 return false;
 }
 return true;
 }

And the HTML:

 <form onsubmit=" return validateForm();" action="myscript.php" id="primary">
 <label>Name<input type="text" id="nm"></input></label>
 <label>Email<input type="text" id="em"></input></label>
 <input type="submit" id="send" value="submit"></input>
 </form>

Answer 1

You should use the == or === (exact equal to) to compare values, the = operator is used to assign values.

 function validateForm() {
 if (document.getElementById("nm").value == "") {
 alert("You must enter a name!"); 
 return false; 
 }
 if (document.getElementById("em").value == "") {
 alert("email required"); 
 return false; 
 }
 return true;
 }

• roshiro: Instead of return false, you need to use event.preventDefault() to stop the form submission.

Answer 2

When making a condition on an if statement the "is equal to" comparison symbol is == or ===. = is used for assigning variables.

Answer 3

There's already an answer for that here -> onsubmit method doesn't stop submit

Basically you need to use event.preventDefault() to stop the form submission.