How to not submit a form if validation is false

How can I make sure the form won't submit if one of the validations is false?

$('#form').submit(function(){
    validateForm1();
    validateForm(document.forms['dpart2']);
    validateForm(document.forms['dpart3']);      
});

From stackoverflow

• If validateForm(...) and validateForm1() return a boolean (true means that no validation error occurred), then you try to do that :

  $('#form').submit(function(){
      if (!validateForm1() || !validateForm(document.forms['dpart2']) || !validateForm(document.forms['dpart3'])) {
          return false;
      }
  });
  

• If the function returns false, form won't be submitted.

  $('#form').submit(function(){
      return  validateForm1() 
              && validateForm(document.forms['dpart2']) 
              && validateForm(document.forms['dpart3']);                                         
                }
  });
  

• $('#form').submit(function(){
      return (validateForm1() &&
              validateForm(document.forms['dpart2']) &&
              validateForm(document.forms['dpart3']))
  });
  

  Basically, you return false in the event handler function.

• A thought that comes up automatically: Even if you implemented thorough client side validation be prepared to receive any invalid request data on the server that you can possibly imagine.

  Client-side validation never keeps you from server-side validation. It is just a bonus in usability.

• Okay, some of the other solutions will have a lazy fail... you probably want all your validation to run, so that all errors are displayed. The presumption is that your validation methods will return false if they fail.

  $("#myform").submit(function() {
  
      var ret = true;
      ret = validateForm1() && ret;
      ret = validateForm(document.forms['dpart2']) && ret
      ret = validateForm(document.forms['dpart3'])) && ret
      return ret;
  
  });

  This way all your validators will be called, but the Boolean value for any failure, will result in a fail.