validation.js 使用实例

   //自定义验证事件
  $.validator.addMethod('checkPro', function (value, element, param) {
        if ($('input[name="is_buy"]:checked').val() == "1") {
            var pro = $("#products").val();
            return pro != "" || pro.length > 0;
        }
        return true;
    }, '<i class="icon-exclamation-sign"></i>请选择产品');

    $('#hezuo_form').validate({
        errorPlacement: function (error, element) {
            if (element.is(':radio') || element.is(':checkbox')) { //如果是radio或checkbox 
                error.appendTo(element.parent()); //将错误信息添加当前元素的父结点后面 
            } else {
                $(element).next('span').append(error);
            }
        },
        onfocusout: function (element) {
            $(element).valid();
        },
        rules: {
            title: {
                required: true,
                minlength: 3,
                maxlength: 50
            }, 
            products: {
                checkPro: true
            }
        },
        messages: {
            title: {
                required: '<i class="icon-exclamation-sign"></i>请填写招募标题',
                minlength: '<i class="icon-exclamation-sign"></i>标题名称长度至少3个字，最长50个字',
                maxlength: '<i class="icon-exclamation-sign"></i>标题名称长度至少3个字，最长50个字'
            } 
        }
    });
});