Integer parameters modified to empty string

// GET method for returning paginated list of CategoryDto objects
        [HttpGet]
        public IActionResult GetCategories(string? searchText, int pageIndex, int pageSize)
        {
            // Call CategoryRepository's method for returning paginated list of CategoryDto objects
            var pagination = unitOfWork.CategoryRepository.GetFilteredCategories(searchText ?? string.Empty, pageIndex, pageSize);

            // Return status code 200 along with list of CategoryDto objects
            return Ok(pagination);
        }

// CategoryRepository method

public Pagination<CategoryDto> GetFilteredCategories(string searchText, int pageIndex, int pageSize)
        {
            var allCategories = context.Categories.AsQueryable();

            if (!string.IsNullOrEmpty(searchText))
            {
                allCategories = allCategories.Where(e => e.Code.ToLower().Contains(searchText.ToLower())
                                                || e.Name.ToLower().Contains(searchText.ToLower()));
            }

            //Variable that will contain CategoryDto objects
            List<CategoryDto> categoryDtos = new();

            // Iterate through allCategories and populate categoryDtos
            // using Category's extension method ConvertToDto()
            foreach (var category in allCategories)
            {
                categoryDtos.Add(category.ConvertToDto());
            }

            // Using PaginationUtility's GetPaginatedResult() method, 
            // return Pagionation<CategoryDto> object
            return PaginationUtility<CategoryDto>.GetPaginatedResult(in categoryDtos, pageIndex, pageSize);
        }