MVC Custom Validation for List on Client Side

by

The reason you will not get client side validation is because the html helpers generate data-val-* attributes for controls associated with properties. jquery.validate.unobtrusive reads those attributes when the form is parsed and using rules, displays an error message in the appropriate element generated by ValidationMessageFor() associated with that control (it does this by matching up the id attributes of the elements – the error message is generated in a span with <span for="TheIdOfTheAssociatedControl" ...>).

You don’t (and cant) generate a control for property DeclarationQuestions (only for properties of each item in DeclarationQuestions so there is nothing that can be matched up.

You could handle this by including your own error message placeholder and intercepting the .submit event

html (add css to style #conditions-error as display:none;)

<span id="delarations-error" class="field-validation-error">
  <span>You must accept all declarations to continue.</span>
</span>

Script

var declarationsError = $('#delarations-error');
$('form').submit(function() {
  var isValid = $('.yourCheckBoxClass').not(':checked') == 0;
  if(!isValid) {
    declarationsError.show(); // display error message
    return false; // prevent submit
  }
});

$('.yourCheckBoxClass').change(function() {
  if($(this).is(':checked')) {
    declarationsError.hide(); // hide error message
  }
});

Side note: You loop for generating the checkboxes should be

for (int i = 0; i < Model.DeclarationQuestions.Count; i++)
{
  @Html.CheckBoxFor(m => m.DeclarationQuestions[i].Answer, new { id = "DeclarationQuestions" + i})
}

More Related Contents:

  1. How to determine if using MVC4 vs MVC5 vs MVC6? [closed]
  2. How to use sessions in an ASP.NET MVC 4 application?
  3. MVC4 DataType.Date EditorFor won’t display date value in Chrome, fine in Internet Explorer
  4. How to add Web API to an existing ASP.NET MVC 4 Web Application project?
  5. Can we pass model as a parameter in RedirectToAction?
  6. Adding another “Pet” to a Model Form
  7. Unity Inject dependencies into MVC filter class with parameters
  8. The anti-forgery token could not be decrypted
  9. Why is Model Binding not working in my POST action method?
  10. Razor View throwing “The name ‘model’ does not exist in the current context”
  11. Why is my CSS bundling not working with a bin deployed MVC4 app?
  12. Display DateTime value in dd/mm/yyyy format in Asp.NET MVC
  13. ASP.NET MVC 4 intercept all incoming requests
  14. How can I pass parameters to a partial view in mvc 4
  15. ASP.NET MVC framework 4.5 CSS bundle does not work on the hosting
  16. Is there any good reason to use FormCollection instead of ViewModel?
  17. Razor actionlink autogenerating ?length=7 in URL?
  18. How to link HTML5 form action to Controller ActionResult method in ASP.NET MVC 4
  19. asp.net mvc keep object alive, information
  20. WebAPI Delete not working – 405 Method Not Allowed
  21. Why is DisplayFormat DataFormatString not working?
  22. MVC4 enum and radio button list
  23. MVC4 Scaffolding Add Controller gives error “Unable to retrieve metadata…”
  24. How to create two footer rows in jqgrid
  25. upgrading from MVC4 to MVC5
  26. Routing in Asp.net Mvc 4 and Web Api
  27. MVC 4 ignores DefaultModelBinder.ResourceClassKey
  28. MVC 4 how to validate a non-US date with client validation?
  29. Include all files in a folder in a single bundle
  30. Should I use AsyncController at ASP.NET MVC 4?

Leave a Comment