问题是您已将required规则构建到自定义方法中.

The problem is that you've built the required rule into your custom method.

$.validator.addMethod("refDataAcInput", function(value, element) {
    return ($(element).val() == "" || $(element).data("hasValidSelectedValue") != null);
}, "The item must be a valid selected item.");

删除$(element).val() == ""并替换为this.optional(element) ...

Remove $(element).val() == "" and replace with this.optional(element)...

$.validator.addMethod("refDataAcInput", function(value, element) {
    return (this.optional(element) || $(element).data("hasValidSelectedValue") != null);
}, "The item must be a valid selected item.");

然后，如果您还希望该字段为required，只需声明required规则以及自定义的refDataAcInput规则即可.

Then if you also want the field to be required, just declare the required rule along with your custom refDataAcInput rule.

该插件的默认懒惰"验证现在应该可以按预期工作.

The plugin's default "Lazy" validation should now be working as expected.