Jquery Validation for Two Dropdown Boxes [duplicate]

问题

This question already has answers here:

jQuery Validate Plugin - How to create a simple custom rule? (7 answers)

Closed 4 years ago.

I have Two dropdown boxes, if i select 4 from first select box, the value of the second dropdown value must be less than the first dropdown. if it fails show a custom error message, like that.

<select name="t_dropdown" id="t_dropdown" class="form-control required">
  <option value="">Select Value</option>
  <option value="1">1</option>
  <option value="2">2</option>
  <option value="3">3</option>
  <option value="4">4</option>
  <option value="5">5</option>
</select>

<select name="p_dropdown" id="p_dropdown" class="form-control required">
  <option value="">Select Value</option>
  <option value="1">1</option>
  <option value="2">2</option>
  <option value="3">3</option>
  <option value="4">4</option>
  <option value="5">5</option>
  <option value="6">6</option>
  <option value=">6">>6</option>
</select>

Please let me know, how to do it using jquery validations.

回答1:

You can use jQuery.validator.addMethod-

$.validator.addMethod("matchValue", function (value, element) {
   if($('#t_dropdown').val()==4)
   {
       return value < 4;
   }
    else
    {
        return true;
    }

}, 'Invalid Value');

Demo

来源：https://stackoverflow.com/questions/30978949/jquery-validation-for-two-dropdown-boxes