Force user to fill all fields before enabling form submit

Question

I have a form containing various fields.

See jsFiddle demo.

My aim is to enable the submit button only when the user has filled in all fields.

So far,

Answer 1

• Make the changes take effect after changing inputs values:

On each input change, test the values of other inputs and checked state of radio, if all inputs has been entered it will make the submit button enabled:

var validateInputs = function validateInputs(inputs) {
  var validForm = true;
  inputs.each(function(index) {
    var input = $(this);
    if (!input.val() || (input.type === "radio" && !input.is(':checked'))) {
      $("#subnewtide").attr("disabled", "disabled");
      validForm = false;
    }
  });
  return validForm;
}

inputs.change(function() {
  if (validateInputs(inputs)) {
    $("#subnewtide").removeAttr("disabled");
  }
});

Demo:

var inputs = $("form#myForm input, form#myForm textarea");

var validateInputs = function validateInputs(inputs) {
  var validForm = true;
  inputs.each(function(index) {
    var input = $(this);
    if (!input.val() || (input.type === "radio" && !input.is(':checked'))) {
      $("#subnewtide").attr("disabled", "disabled");
      validForm = false;
    }
  });
  return validForm;
}


inputs.change(function() {
  if (validateInputs(inputs)) {
    $("#subnewtide").removeAttr("disabled");
  }
});

  Title:
  
  
Description:
  
  
Tag:
  
  
Category:
  Animation
  Submit

Also it uses the form id="myForm", so you can use it to validate only specific forms in your pages.

Note: This is tested and working on Chrome, Firefox and IE.

---

EDIT:

• Make the changes take effect when we type in the inputs:

In the previous code we are using onchange event handler to call the function so it's only called when we click outside a given input (after change).

To perform the call automatically when the user enters a character in a field (the last one) we need to use the onkeyup event so we don't need to click outside of it.

This is the changed code you need :

    var inputs = $("form#myForm input, form#myForm textarea");

    var validateInputs = function validateInputs(inputs) {
      var validForm = true;
      inputs.each(function(index) {
        var input = $(this);
        if (!input.val() || (input.type === "radio" && !input.is(':checked'))) {
          $("#subnewtide").attr("disabled", "disabled");
          validForm = false;
        }
      });
      return validForm;
    }


    inputs.each(function() {
      var input = $(this);
      if (input.type === "radio") {
        input.change(function() {
          if (validateInputs(inputs)) {
            $("#subnewtide").removeAttr("disabled");
          }
        });
      } else {
        input.keyup(function() {
          if (validateInputs(inputs)) {
            $("#subnewtide").removeAttr("disabled");
          }
        });
      }
    });

  Title:
  
  
Description:
  
  
Tag:
  
  
Category:
  Animation
  Submit