public class CheckBoxRequired : ValidationAttribute, IClientModelValidator
    {
        public override bool IsValid(object value)
        {
            if (value is bool)
            {
                return (bool)value;
            }
 
            return false;
        }
 
        public void AddValidation(ClientModelValidationContext context)
        {
            context.Attributes.Add("data-val-checkboxrequired", FormatErrorMessage(context.ModelMetadata.GetDisplayName()));
        }
    }

public class PersonModel
{
    [Display(Name = "I accept the above terms and conditions.")]
    [CheckBoxRequired(ErrorMessage = "Please accept the terms and condition.")]
    public bool TermsConditions { get; set; }
}

<script type="text/javascript">
       (function ($) {
           $.validator.unobtrusive.adapters.addBool("checkboxrequired", "required");
       }(jQuery));
   </script>

 參考文獻

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